src/sysdep.c

   1 /* Interfaces to system-dependent kernel and library entries.
   2    Copyright (C) 1985, 86, 87, 88, 93, 94 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20
  21 #include <signal.h>
  22 #include <setjmp.h>
  23
  24 #include <config.h>
  25 #include "lisp.h"
  26 #include "blockinput.h"
  27 #undef NULL
  28
  29 #define min(x,y) ((x) > (y) ? (y) : (x))
  30
  31 /* In this file, open, read and write refer to the system calls,
  32    not our sugared interfaces  sys_open, sys_read and sys_write.
  33    Contrariwise, for systems where we use the system calls directly,
  34    define sys_read, etc. here as aliases for them.  */
  35 #ifndef read
  36 #define sys_read read
  37 #define sys_write write
  38 #endif /* `read' is not a macro */
  39
  40 #undef read
  41 #undef write
  42
  43 #ifndef close
  44 #define sys_close close
  45 #else
  46 #undef close
  47 #endif
  48
  49 #ifndef open
  50 #define sys_open open
  51 #else /* `open' is a macro */
  52 #undef open
  53 #endif /* `open' is a macro */
  54
  55 /* Does anyone other than VMS need this? */
  56 #ifndef fwrite
  57 #define sys_fwrite fwrite
  58 #else
  59 #undef fwrite
  60 #endif
  61
  62 #ifndef HAVE_H_ERRNO
  63 extern int h_errno;
  64 #endif
  65
  66 #include <stdio.h>
  67 #include <sys/types.h>
  68 #include <sys/stat.h>
  69 #include <errno.h>
  70
  71 #ifdef MSDOS    /* Demacs 1.1.2 91/10/20 Manabu Higashida, MW Aug 1993 */
  72 #include <dos.h>
  73 #include "dosfns.h"
  74 #include "msdos.h"
  75 #include <sys/param.h>
  76 #endif
  77
  78 extern int errno;
  79
  80 #ifdef VMS
  81 #include <rms.h>
  82 #include <ttdef.h>
  83 #include <tt2def.h>
  84 #include <iodef.h>
  85 #include <ssdef.h>
  86 #include <descrip.h>
  87 #include <fibdef.h>
  88 #include <atrdef.h>
  89 #include <ctype.h>
  90 #include <string.h>
  91 #ifdef __GNUC__
  92 #include <sys/file.h>
  93 #else
  94 #include <file.h>
  95 #endif
  96 #undef F_SETFL
  97 #ifndef RAB$C_BID
  98 #include <rab.h>
  99 #endif
 100 #define MAXIOSIZE ( 32 * PAGESIZE )     /* Don't I/O more than 32 blocks at a time */
 101 #endif /* VMS */
 102
 103 #ifndef BSD4_1
 104 #ifdef BSD /* this is done this way to avoid defined (BSD) || defined (USG)
 105               because the vms compiler doesn't grok `defined' */
 106 #include <fcntl.h>
 107 #endif
 108 #ifdef USG
 109 #ifndef USG5
 110 #include <fcntl.h>
 111 #endif
 112 #endif
 113 #endif /* not 4.1 bsd */
 114
 115 #ifndef MSDOS
 116 #include <sys/ioctl.h>
 117 #endif
 118 #include "systty.h"
 119 #include "syswait.h"
 120
 121 #ifdef BROKEN_TIOCGWINSZ
 122 #undef TIOCGWINSZ
 123 #undef TIOCSWINSZ
 124 #endif
 125
 126 #ifdef USG
 127 #include <sys/utsname.h>
 128 #include <string.h>
 129 #ifndef MEMORY_IN_STRING_H
 130 #include <memory.h>
 131 #endif
 132 #if defined (TIOCGWINSZ) || defined (ISC4_0)
 133 #ifdef NEED_SIOCTL
 134 #include <sys/sioctl.h>
 135 #endif
 136 #ifdef NEED_PTEM_H
 137 #include <sys/stream.h>
 138 #include <sys/ptem.h>
 139 #endif
 140 #endif /* TIOCGWINSZ or ISC4_0 */
 141 #endif /* USG */
 142
 143 extern int quit_char;
 144
 145 #include "frame.h"
 146 #include "window.h"
 147 #include "termhooks.h"
 148 #include "termchar.h"
 149 #include "termopts.h"
 150 #include "dispextern.h"
 151 #include "process.h"
 152
 153 #ifdef NONSYSTEM_DIR_LIBRARY
 154 #include "ndir.h"
 155 #endif /* NONSYSTEM_DIR_LIBRARY */
 156
 157 #include "syssignal.h"
 158 #include "systime.h"
 159 #ifdef HAVE_UTIME_H
 160 #include <utime.h>
 161 #endif
 162
 163 #ifndef HAVE_UTIMES
 164 #ifndef HAVE_STRUCT_UTIMBUF
 165 /* We want to use utime rather than utimes, but we couldn't find the
 166    structure declaration.  We'll use the traditional one.  */
 167 struct utimbuf {
 168   long actime;
 169   long modtime;
 170 };
 171 #endif
 172 #endif
 173
 174 /* LPASS8 is new in 4.3, and makes cbreak mode provide all 8 bits.  */
 175 #ifndef LPASS8
 176 #define LPASS8 0
 177 #endif
 178
 179 #ifdef BSD4_1
 180 #define LNOFLSH 0100000
 181 #endif
 182
 183 static int baud_convert[] =
 184 #ifdef BAUD_CONVERT
 185   BAUD_CONVERT;
 186 #else
 187   {
 188     0, 50, 75, 110, 135, 150, 200, 300, 600, 1200,
 189     1800, 2400, 4800, 9600, 19200, 38400
 190   };
 191 #endif
 192
 193 extern short ospeed;
 194
 195 /* The file descriptor for Emacs's input terminal.
 196    Under Unix, this is normally zero except when using X;
 197    under VMS, we place the input channel number here.  */
 198 int input_fd;
 199 \f
 200 /* Specify a different file descriptor for further input operations.  */
 201
 202 void
 203 change_input_fd (fd)
 204      int fd;
 205 {
 206   input_fd = fd;
 207 }
 208
 209 /* Discard pending input on descriptor input_fd.  */
 210
 211 discard_tty_input ()
 212 {
 213   struct emacs_tty buf;
 214
 215   if (noninteractive)
 216     return;
 217
 218   /* Discarding input is not safe when the input could contain
 219      replies from the X server.  So don't do it.  */
 220   if (read_socket_hook)
 221     return;
 222
 223 #ifdef VMS
 224   end_kbd_input ();
 225   SYS$QIOW (0, input_fd, IO$_READVBLK|IO$M_PURGE, input_iosb, 0, 0,
 226             &buf.main, 0, 0, terminator_mask, 0, 0);
 227   queue_kbd_input ();
 228 #else /* not VMS */
 229 #ifdef APOLLO
 230   {
 231     int zero = 0;
 232     ioctl (input_fd, TIOCFLUSH, &zero);
 233   }
 234 #else /* not Apollo */
 235 #ifdef MSDOS    /* Demacs 1.1.1 91/10/16 HIRANO Satoshi */
 236   while (dos_keyread () != -1)
 237         ;
 238 #else /* not MSDOS */
 239   EMACS_GET_TTY (input_fd, &buf);
 240   EMACS_SET_TTY (input_fd, &buf, 0);
 241 #endif /* not MSDOS */
 242 #endif /* not Apollo */
 243 #endif /* not VMS */
 244 }
 245
 246 #ifdef SIGTSTP
 247
 248 /* Arrange for character C to be read as the next input from
 249    the terminal.  */
 250
 251 stuff_char (c)
 252      char c;
 253 {
 254 /* Should perhaps error if in batch mode */
 255 #ifdef TIOCSTI
 256   ioctl (input_fd, TIOCSTI, &c);
 257 #else /* no TIOCSTI */
 258   error ("Cannot stuff terminal input characters in this version of Unix");
 259 #endif /* no TIOCSTI */
 260 }
 261
 262 #endif /* SIGTSTP */
 263 \f
 264 init_baud_rate ()
 265 {
 266   if (noninteractive)
 267     ospeed = 0;
 268   else
 269     {
 270 #ifdef MSDOS
 271     ospeed = 15;
 272 #else
 273 #ifdef VMS
 274       struct sensemode sg;
 275
 276       SYS$QIOW (0, input_fd, IO$_SENSEMODE, &sg, 0, 0,
 277                 &sg.class, 12, 0, 0, 0, 0 );
 278       ospeed = sg.xmit_baud;
 279 #else /* not VMS */
 280 #ifdef HAVE_TERMIOS
 281       struct termios sg;
 282
 283       sg.c_cflag = B9600;
 284       tcgetattr (input_fd, &sg);
 285       ospeed = cfgetospeed (&sg);
 286 #if defined (USE_GETOBAUD) && defined (getobaud)
 287       /* m88k-motorola-sysv3 needs this (ghazi@noc.rutgers.edu) 9/1/94. */
 288       if (ospeed == 0)
 289         ospeed = getobaud (sg.c_cflag);
 290 #endif
 291 #else /* neither VMS nor TERMIOS */
 292 #ifdef HAVE_TERMIO
 293       struct termio sg;
 294
 295       sg.c_cflag = B9600;
 296 #ifdef HAVE_TCATTR
 297       tcgetattr (input_fd, &sg);
 298 #else
 299       ioctl (input_fd, TCGETA, &sg);
 300 #endif
 301       ospeed = sg.c_cflag & CBAUD;
 302 #else /* neither VMS nor TERMIOS nor TERMIO */
 303       struct sgttyb sg;
 304
 305       sg.sg_ospeed = B9600;
 306       if (ioctl (input_fd, TIOCGETP, &sg) < 0)
 307         abort ();
 308       ospeed = sg.sg_ospeed;
 309 #endif /* not HAVE_TERMIO */
 310 #endif /* not HAVE_TERMIOS */
 311 #endif /* not VMS */
 312 #endif /* not MSDOS */
 313     }
 314
 315   baud_rate = (ospeed < sizeof baud_convert / sizeof baud_convert[0]
 316                ? baud_convert[ospeed] : 9600);
 317   if (baud_rate == 0)
 318     baud_rate = 1200;
 319 }
 320
 321 /*ARGSUSED*/
 322 set_exclusive_use (fd)
 323      int fd;
 324 {
 325 #ifdef FIOCLEX
 326   ioctl (fd, FIOCLEX, 0);
 327 #endif
 328   /* Ok to do nothing if this feature does not exist */
 329 }
 330 \f
 331 #ifndef subprocesses
 332
 333 wait_without_blocking ()
 334 {
 335 #ifdef BSD
 336   wait3 (0, WNOHANG | WUNTRACED, 0);
 337 #else
 338   croak ("wait_without_blocking");
 339 #endif
 340   synch_process_alive = 0;
 341 }
 342
 343 #endif /* not subprocesses */
 344
 345 int wait_debugging;   /* Set nonzero to make following function work under dbx
 346                          (at least for bsd).  */
 347
 348 SIGTYPE
 349 wait_for_termination_signal ()
 350 {}
 351
 352 /* Wait for subprocess with process id `pid' to terminate and
 353    make sure it will get eliminated (not remain forever as a zombie) */
 354
 355 wait_for_termination (pid)
 356      int pid;
 357 {
 358   while (1)
 359     {
 360 #ifdef subprocesses
 361 #ifdef VMS
 362       int status;
 363
 364       status = SYS$FORCEX (&pid, 0, 0);
 365       break;
 366 #else /* not VMS */
 367 #if defined (BSD) || (defined (HPUX) && !defined (HPUX_5))
 368       /* Note that kill returns -1 even if the process is just a zombie now.
 369          But inevitably a SIGCHLD interrupt should be generated
 370          and child_sig will do wait3 and make the process go away. */
 371       /* There is some indication that there is a bug involved with
 372          termination of subprocesses, perhaps involving a kernel bug too,
 373          but no idea what it is.  Just as a hunch we signal SIGCHLD to see
 374          if that causes the problem to go away or get worse.  */
 375       sigsetmask (sigmask (SIGCHLD));
 376       if (0 > kill (pid, 0))
 377         {
 378           sigsetmask (SIGEMPTYMASK);
 379           kill (getpid (), SIGCHLD);
 380           break;
 381         }
 382       if (wait_debugging)
 383         sleep (1);
 384       else
 385         sigpause (SIGEMPTYMASK);
 386 #else /* not BSD, and not HPUX version >= 6 */
 387 #if defined (UNIPLUS)
 388       if (0 > kill (pid, 0))
 389         break;
 390       wait (0);
 391 #else /* neither BSD nor UNIPLUS: random sysV */
 392 #ifdef POSIX_SIGNALS    /* would this work for LINUX as well? */
 393       sigblock (sigmask (SIGCHLD));
 394       if (0 > kill (pid, 0))
 395         {
 396           sigunblock (sigmask (SIGCHLD));
 397           break;
 398         }
 399       sigpause (SIGEMPTYMASK);
 400 #else /* not POSIX_SIGNALS */
 401 #ifdef HAVE_SYSV_SIGPAUSE
 402       sighold (SIGCHLD);
 403       if (0 > kill (pid, 0))
 404         {
 405           sigrelse (SIGCHLD);
 406           break;
 407         }
 408       sigpause (SIGCHLD);
 409 #else /* not HAVE_SYSV_SIGPAUSE */
 410       if (0 > kill (pid, 0))
 411         break;
 412       /* Using sleep instead of pause avoids timing error.
 413          If the inferior dies just before the sleep,
 414          we lose just one second.  */
 415       sleep (1);
 416 #endif /* not HAVE_SYSV_SIGPAUSE */
 417 #endif /* not POSIX_SIGNALS */
 418 #endif /* not UNIPLUS */
 419 #endif /* not BSD, and not HPUX version >= 6 */
 420 #endif /* not VMS */
 421 #else /* not subprocesses */
 422 #ifndef BSD4_1
 423       if (kill (pid, 0) < 0)
 424         break;
 425       wait (0);
 426 #else /* BSD4_1 */
 427       int status;
 428       status = wait (0);
 429       if (status == pid || status == -1)
 430         break;
 431 #endif /* BSD4_1 */
 432 #endif /* not subprocesses */
 433     }
 434 }
 435
 436 #ifdef subprocesses
 437
 438 /*
 439  *      flush any pending output
 440  *      (may flush input as well; it does not matter the way we use it)
 441  */
 442
 443 flush_pending_output (channel)
 444      int channel;
 445 {
 446 #ifdef HAVE_TERMIOS
 447   /* If we try this, we get hit with SIGTTIN, because
 448      the child's tty belongs to the child's pgrp. */
 449 #else
 450 #ifdef TCFLSH
 451   ioctl (channel, TCFLSH, 1);
 452 #else
 453 #ifdef TIOCFLUSH
 454   int zero = 0;
 455   /* 3rd arg should be ignored
 456      but some 4.2 kernels actually want the address of an int
 457      and nonzero means something different.  */
 458   ioctl (channel, TIOCFLUSH, &zero);
 459 #endif
 460 #endif
 461 #endif
 462 }
 463 \f
 464 #ifndef VMS
 465 /*  Set up the terminal at the other end of a pseudo-terminal that
 466     we will be controlling an inferior through.
 467     It should not echo or do line-editing, since that is done
 468     in Emacs.  No padding needed for insertion into an Emacs buffer.  */
 469
 470 child_setup_tty (out)
 471      int out;
 472 {
 473 #ifndef MSDOS
 474   struct emacs_tty s;
 475
 476   EMACS_GET_TTY (out, &s);
 477
 478 #if defined (HAVE_TERMIO) || defined (HAVE_TERMIOS)
 479   s.main.c_oflag |= OPOST;      /* Enable output postprocessing */
 480   s.main.c_oflag &= ~ONLCR;     /* Disable map of NL to CR-NL on output */
 481 #ifdef NLDLY
 482   s.main.c_oflag &= ~(NLDLY|CRDLY|TABDLY|BSDLY|VTDLY|FFDLY);
 483                                 /* No output delays */
 484 #endif
 485   s.main.c_lflag &= ~ECHO;      /* Disable echo */
 486   s.main.c_lflag |= ISIG;       /* Enable signals */
 487 #ifdef IUCLC
 488   s.main.c_iflag &= ~IUCLC;     /* Disable downcasing on input.  */
 489 #endif
 490 #ifdef OLCUC
 491   s.main.c_oflag &= ~OLCUC;     /* Disable upcasing on output.  */
 492 #endif
 493   s.main.c_cflag = (s.main.c_cflag & ~CSIZE) | CS8; /* Don't strip 8th bit */
 494 #if 0
 495   /* Said to be unnecessary:  */
 496   s.main.c_cc[VMIN] = 1;        /* minimum number of characters to accept  */
 497   s.main.c_cc[VTIME] = 0;       /* wait forever for at least 1 character  */
 498 #endif
 499
 500   s.main.c_lflag |= ICANON;     /* Enable erase/kill and eof processing */
 501   s.main.c_cc[VEOF] = 04;       /* insure that EOF is Control-D */
 502   s.main.c_cc[VERASE] = 0377;   /* disable erase processing */
 503   s.main.c_cc[VKILL] = 0377;    /* disable kill processing */
 504
 505 #ifdef HPUX
 506   s.main.c_cflag = (s.main.c_cflag & ~CBAUD) | B9600; /* baud rate sanity */
 507 #endif /* HPUX */
 508
 509 #ifdef AIX
 510 /* AIX enhanced edit loses NULs, so disable it */
 511 #ifndef IBMR2AIX
 512   s.main.c_line = 0;
 513   s.main.c_iflag &= ~ASCEDIT;
 514 #endif
 515   /* Also, PTY overloads NUL and BREAK.
 516      don't ignore break, but don't signal either, so it looks like NUL.  */
 517   s.main.c_iflag &= ~IGNBRK;
 518   s.main.c_iflag &= ~BRKINT;
 519   /* QUIT and INTR work better as signals, so disable character forms */
 520   s.main.c_cc[VINTR] = 0377;
 521 #ifdef SIGNALS_VIA_CHARACTERS
 522   /* the QUIT and INTR character are used in process_send_signal
 523      so set them here to something useful.  */
 524   if (s.main.c_cc[VQUIT] == 0377)
 525     s.main.c_cc[VQUIT] = '\\'&037;      /* Control-\ */
 526   if (s.main.c_cc[VINTR] == 0377)
 527     s.main.c_cc[VINTR] = 'C'&037;       /* Control-C */
 528 #else /* no TIOCGPGRP or no TIOCGLTC or no TIOCGETC */
 529   /* QUIT and INTR work better as signals, so disable character forms */
 530   s.main.c_cc[VQUIT] = 0377;
 531   s.main.c_cc[VINTR] = 0377;
 532   s.main.c_lflag &= ~ISIG;
 533 #endif /* no TIOCGPGRP or no TIOCGLTC or no TIOCGETC */
 534   s.main.c_cc[VEOL] = 0377;
 535   s.main.c_cflag = (s.main.c_cflag & ~CBAUD) | B9600; /* baud rate sanity */
 536 #endif /* AIX */
 537
 538 #else /* not HAVE_TERMIO */
 539
 540   s.main.sg_flags &= ~(ECHO | CRMOD | ANYP | ALLDELAY | RAW | LCASE
 541                        | CBREAK | TANDEM);
 542   s.main.sg_flags |= LPASS8;
 543   s.main.sg_erase = 0377;
 544   s.main.sg_kill = 0377;
 545   s.lmode = LLITOUT | s.lmode;        /* Don't strip 8th bit */
 546
 547 #endif /* not HAVE_TERMIO */
 548
 549   EMACS_SET_TTY (out, &s, 0);
 550
 551 #ifdef BSD4_1
 552   if (interrupt_input)
 553     reset_sigio ();
 554 #endif /* BSD4_1 */
 555 #ifdef RTU
 556   {
 557     int zero = 0;
 558     ioctl (out, FIOASYNC, &zero);
 559   }
 560 #endif /* RTU */
 561 #endif /* not MSDOS */
 562 }
 563 #endif /* not VMS */
 564
 565 #endif /* subprocesses */
 566
 567 /*ARGSUSED*/
 568 setpgrp_of_tty (pid)
 569      int pid;
 570 {
 571   EMACS_SET_TTY_PGRP (input_fd, &pid);
 572 }
 573 \f
 574 /* Record a signal code and the handler for it.  */
 575 struct save_signal
 576 {
 577   int code;
 578   SIGTYPE (*handler) ();
 579 };
 580
 581 /* Suspend the Emacs process; give terminal to its superior.  */
 582
 583 sys_suspend ()
 584 {
 585 #ifdef VMS
 586   /* "Foster" parentage allows emacs to return to a subprocess that attached
 587      to the current emacs as a cheaper than starting a whole new process.  This
 588      is set up by KEPTEDITOR.COM.  */
 589   unsigned long parent_id, foster_parent_id;
 590   char *fpid_string;
 591
 592   fpid_string = getenv ("EMACS_PARENT_PID");
 593   if (fpid_string != NULL)
 594     {
 595       sscanf (fpid_string, "%x", &foster_parent_id);
 596       if (foster_parent_id != 0)
 597         parent_id = foster_parent_id;
 598       else
 599         parent_id = getppid ();
 600     }
 601   else
 602     parent_id = getppid ();
 603
 604   xfree (fpid_string);          /* On VMS, this was malloc'd */
 605
 606   if (parent_id && parent_id != 0xffffffff)
 607     {
 608       SIGTYPE (*oldsig)() = (int) signal (SIGINT, SIG_IGN);
 609       int status = LIB$ATTACH (&parent_id) & 1;
 610       signal (SIGINT, oldsig);
 611       return status;
 612     }
 613   else
 614     {
 615       struct {
 616         int     l;
 617         char    *a;
 618       } d_prompt;
 619       d_prompt.l = sizeof ("Emacs: ");          /* Our special prompt */
 620       d_prompt.a = "Emacs: ";                   /* Just a reminder */
 621       LIB$SPAWN (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, &d_prompt, 0);
 622       return 1;
 623     }
 624   return -1;
 625 #else
 626 #if defined(SIGTSTP) && !defined(MSDOS)
 627
 628   {
 629     int pgrp = EMACS_GETPGRP (0);
 630     EMACS_KILLPG (pgrp, SIGTSTP);
 631   }
 632
 633 #else /* No SIGTSTP */
 634 #ifdef USG_JOBCTRL /* If you don't know what this is don't mess with it */
 635   ptrace (0, 0, 0, 0);          /* set for ptrace - caught by csh */
 636   kill (getpid (), SIGQUIT);
 637
 638 #else /* No SIGTSTP or USG_JOBCTRL */
 639
 640 /* On a system where suspending is not implemented,
 641    instead fork a subshell and let it talk directly to the terminal
 642    while we wait.  */
 643   sys_subshell ();
 644
 645 #endif /* no USG_JOBCTRL */
 646 #endif /* no SIGTSTP */
 647 #endif /* not VMS */
 648 }
 649
 650 /* Fork a subshell.  */
 651
 652 sys_subshell ()
 653 {
 654 #ifndef VMS
 655 #ifdef MSDOS    /* Demacs 1.1.2 91/10/20 Manabu Higashida */
 656   int st;
 657   char oldwd[MAXPATHLEN+1]; /* Fixed length is safe on MSDOS.  */
 658 #endif
 659   int pid;
 660   struct save_signal saved_handlers[5];
 661   Lisp_Object dir;
 662   unsigned char *str = 0;
 663   int len;
 664
 665   saved_handlers[0].code = SIGINT;
 666   saved_handlers[1].code = SIGQUIT;
 667   saved_handlers[2].code = SIGTERM;
 668 #ifdef SIGIO
 669   saved_handlers[3].code = SIGIO;
 670   saved_handlers[4].code = 0;
 671 #else
 672   saved_handlers[3].code = 0;
 673 #endif
 674
 675   /* Mentioning current_buffer->buffer would mean including buffer.h,
 676      which somehow wedges the hp compiler.  So instead...  */
 677
 678   dir = intern ("default-directory");
 679   if (NILP (Fboundp (dir)))
 680     goto xyzzy;
 681   dir = Fsymbol_value (dir);
 682   if (!STRINGP (dir))
 683     goto xyzzy;
 684
 685   dir = expand_and_dir_to_file (Funhandled_file_name_directory (dir), Qnil);
 686   str = (unsigned char *) alloca (XSTRING (dir)->size + 2);
 687   len = XSTRING (dir)->size;
 688   bcopy (XSTRING (dir)->data, str, len);
 689   if (str[len - 1] != '/') str[len++] = '/';
 690   str[len] = 0;
 691  xyzzy:
 692
 693   pid = vfork ();
 694
 695   if (pid == -1)
 696     error ("Can't spawn subshell");
 697   if (pid == 0)
 698     {
 699       char *sh;
 700
 701 #ifdef MSDOS    /* MW, Aug 1993 */
 702       getwd (oldwd);
 703 #endif
 704       sh = (char *) egetenv ("SHELL");
 705       if (sh == 0)
 706         sh = "sh";
 707
 708       /* Use our buffer's default directory for the subshell.  */
 709       if (str)
 710         chdir (str);
 711
 712 #ifdef subprocesses
 713       close_process_descs ();   /* Close Emacs's pipes/ptys */
 714 #endif
 715
 716 #ifdef SET_EMACS_PRIORITY
 717       {
 718         extern int emacs_priority;
 719
 720         if (emacs_priority < 0)
 721           nice (-emacs_priority);
 722       }
 723 #endif
 724
 725 #ifdef MSDOS    /* Demacs 1.1.2 91/10/20 Manabu Higashida */
 726       st = system (sh);
 727       chdir (oldwd);
 728       if (st)
 729         report_file_error ("Can't execute subshell", Fcons (build_string (sh), Qnil));
 730 #else /* not MSDOS */
 731       execlp (sh, sh, 0);
 732       write (1, "Can't execute subshell", 22);
 733       _exit (1);
 734 #endif /* not MSDOS */
 735     }
 736
 737   save_signal_handlers (saved_handlers);
 738   synch_process_alive = 1;
 739   wait_for_termination (pid);
 740   restore_signal_handlers (saved_handlers);
 741 #endif /* !VMS */
 742 }
 743
 744 save_signal_handlers (saved_handlers)
 745      struct save_signal *saved_handlers;
 746 {
 747   while (saved_handlers->code)
 748     {
 749       saved_handlers->handler
 750         = (SIGTYPE (*) ()) signal (saved_handlers->code, SIG_IGN);
 751       saved_handlers++;
 752     }
 753 }
 754
 755 restore_signal_handlers (saved_handlers)
 756      struct save_signal *saved_handlers;
 757 {
 758   while (saved_handlers->code)
 759     {
 760       signal (saved_handlers->code, saved_handlers->handler);
 761       saved_handlers++;
 762     }
 763 }
 764 \f
 765 #ifdef F_SETFL
 766
 767 int old_fcntl_flags;
 768
 769 init_sigio ()
 770 {
 771 #ifdef FASYNC
 772   old_fcntl_flags = fcntl (input_fd, F_GETFL, 0) & ~FASYNC;
 773 #endif
 774   request_sigio ();
 775 }
 776
 777 reset_sigio ()
 778 {
 779   unrequest_sigio ();
 780 }
 781
 782 #ifdef FASYNC           /* F_SETFL does not imply existence of FASYNC */
 783
 784 request_sigio ()
 785 {
 786 #ifdef SIGWINCH
 787   sigunblock (sigmask (SIGWINCH));
 788 #endif
 789   fcntl (input_fd, F_SETFL, old_fcntl_flags | FASYNC);
 790
 791   interrupts_deferred = 0;
 792 }
 793
 794 unrequest_sigio ()
 795 {
 796 #ifdef SIGWINCH
 797   sigblock (sigmask (SIGWINCH));
 798 #endif
 799   fcntl (input_fd, F_SETFL, old_fcntl_flags);
 800   interrupts_deferred = 1;
 801 }
 802
 803 #else /* no FASYNC */
 804 #ifdef STRIDE           /* Stride doesn't have FASYNC - use FIOASYNC */
 805
 806 request_sigio ()
 807 {
 808   int on = 1;
 809   ioctl (input_fd, FIOASYNC, &on);
 810   interrupts_deferred = 0;
 811 }
 812
 813 unrequest_sigio ()
 814 {
 815   int off = 0;
 816
 817   ioctl (input_fd, FIOASYNC, &off);
 818   interrupts_deferred = 1;
 819 }
 820
 821 #else /* not FASYNC, not STRIDE */
 822
 823 #ifdef _CX_UX
 824
 825 #include <termios.h>
 826
 827 request_sigio ()
 828 {
 829   int on = 1;
 830   sigset_t st;
 831
 832   sigemptyset(&st);
 833   sigaddset(&st, SIGIO);
 834   ioctl (input_fd, FIOASYNC, &on);
 835   interrupts_deferred = 0;
 836   sigprocmask(SIG_UNBLOCK, &st, (sigset_t *)0);
 837 }
 838
 839 unrequest_sigio ()
 840 {
 841   int off = 0;
 842
 843   ioctl (input_fd, FIOASYNC, &off);
 844   interrupts_deferred = 1;
 845 }
 846
 847 #else /* ! _CX_UX */
 848
 849 request_sigio ()
 850 {
 851   croak ("request_sigio");
 852 }
 853
 854 unrequest_sigio ()
 855 {
 856   croak ("unrequest_sigio");
 857 }
 858
 859 #endif /* _CX_UX */
 860 #endif /* STRIDE */
 861 #endif /* FASYNC */
 862 #endif /* F_SETFL */
 863 \f
 864 /* Saving and restoring the process group of Emacs's terminal.  */
 865
 866 #ifdef BSD_PGRPS
 867
 868 /* The process group of which Emacs was a member when it initially
 869    started.
 870
 871    If Emacs was in its own process group (i.e. inherited_pgroup ==
 872    getpid ()), then we know we're running under a shell with job
 873    control (Emacs would never be run as part of a pipeline).
 874    Everything is fine.
 875
 876    If Emacs was not in its own process group, then we know we're
 877    running under a shell (or a caller) that doesn't know how to
 878    separate itself from Emacs (like sh).  Emacs must be in its own
 879    process group in order to receive SIGIO correctly.  In this
 880    situation, we put ourselves in our own pgroup, forcibly set the
 881    tty's pgroup to our pgroup, and make sure to restore and reinstate
 882    the tty's pgroup just like any other terminal setting.  If
 883    inherited_group was not the tty's pgroup, then we'll get a
 884    SIGTTmumble when we try to change the tty's pgroup, and a CONT if
 885    it goes foreground in the future, which is what should happen.  */
 886 int inherited_pgroup;
 887
 888 /* Split off the foreground process group to Emacs alone.
 889    When we are in the foreground, but not started in our own process
 890    group, redirect the TTY to point to our own process group.  We need
 891    to be in our own process group to receive SIGIO properly.  */
 892 narrow_foreground_group ()
 893 {
 894   int me = getpid ();
 895
 896   setpgrp (0, inherited_pgroup);
 897   if (inherited_pgroup != me)
 898     EMACS_SET_TTY_PGRP (input_fd, &me);
 899   setpgrp (0, me);
 900 }
 901
 902 /* Set the tty to our original foreground group.  */
 903 widen_foreground_group ()
 904 {
 905   if (inherited_pgroup != getpid ())
 906     EMACS_SET_TTY_PGRP (input_fd, &inherited_pgroup);
 907   setpgrp (0, inherited_pgroup);
 908 }
 909
 910 #endif /* BSD_PGRPS */
 911 \f
 912 /* Getting and setting emacs_tty structures.  */
 913
 914 /* Set *TC to the parameters associated with the terminal FD.
 915    Return zero if all's well, or -1 if we ran into an error we
 916    couldn't deal with.  */
 917 int
 918 emacs_get_tty (fd, settings)
 919      int fd;
 920      struct emacs_tty *settings;
 921 {
 922   /* Retrieve the primary parameters - baud rate, character size, etcetera.  */
 923 #ifdef HAVE_TCATTR
 924   /* We have those nifty POSIX tcmumbleattr functions.  */
 925   if (tcgetattr (fd, &settings->main) < 0)
 926     return -1;
 927
 928 #else
 929 #ifdef HAVE_TERMIO
 930   /* The SYSV-style interface?  */
 931   if (ioctl (fd, TCGETA, &settings->main) < 0)
 932     return -1;
 933
 934 #else
 935 #ifdef VMS
 936   /* Vehemently Monstrous System?  :-)  */
 937   if (! (SYS$QIOW (0, fd, IO$_SENSEMODE, settings, 0, 0,
 938                    &settings->main.class, 12, 0, 0, 0, 0)
 939          & 1))
 940     return -1;
 941
 942 #else
 943 #ifndef MSDOS
 944   /* I give up - I hope you have the BSD ioctls.  */
 945   if (ioctl (fd, TIOCGETP, &settings->main) < 0)
 946     return -1;
 947 #endif /* not MSDOS */
 948 #endif
 949 #endif
 950 #endif
 951
 952   /* Suivant - Do we have to get struct ltchars data?  */
 953 #ifdef HAVE_LTCHARS
 954   if (ioctl (fd, TIOCGLTC, &settings->ltchars) < 0)
 955     return -1;
 956 #endif
 957
 958   /* How about a struct tchars and a wordful of lmode bits?  */
 959 #ifdef HAVE_TCHARS
 960   if (ioctl (fd, TIOCGETC, &settings->tchars) < 0
 961       || ioctl (fd, TIOCLGET, &settings->lmode) < 0)
 962     return -1;
 963 #endif
 964
 965   /* We have survived the tempest.  */
 966   return 0;
 967 }
 968
 969
 970 /* Set the parameters of the tty on FD according to the contents of
 971    *SETTINGS.  If WAITP is non-zero, we wait for all queued output to
 972    be written before making the change; otherwise, we forget any
 973    queued input and make the change immediately.
 974    Return 0 if all went well, and -1 if anything failed.  */
 975 int
 976 emacs_set_tty (fd, settings, waitp)
 977      int fd;
 978      struct emacs_tty *settings;
 979      int waitp;
 980 {
 981   /* Set the primary parameters - baud rate, character size, etcetera.  */
 982 #ifdef HAVE_TCATTR
 983   int i;
 984   /* We have those nifty POSIX tcmumbleattr functions.
 985      William J. Smith <wjs@wiis.wang.com> writes:
 986      "POSIX 1003.1 defines tcsetattr() to return success if it was
 987      able to perform any of the requested actions, even if some
 988      of the requested actions could not be performed.
 989      We must read settings back to ensure tty setup properly.
 990      AIX requires this to keep tty from hanging occasionally."  */
 991   /* This make sure that we don't loop indefinitely in here.  */
 992   for (i = 0 ; i < 10 ; i++)
 993     if (tcsetattr (fd, waitp ? TCSAFLUSH : TCSADRAIN, &settings->main) < 0)
 994       {
 995         if (errno == EINTR)
 996           continue;
 997         else
 998           return -1;
 999       }
1000     else
1001       {
1002         struct termios new;
1003
1004         /* Get the current settings, and see if they're what we asked for.  */
1005         tcgetattr (fd, &new);
1006         /* We cannot use memcmp on the whole structure here because under
1007          * aix386 the termios structure has some reserved field that may
1008          * not be filled in.
1009          */
1010         if (   new.c_iflag == settings->main.c_iflag
1011             && new.c_oflag == settings->main.c_oflag
1012             && new.c_cflag == settings->main.c_cflag
1013             && new.c_lflag == settings->main.c_lflag
1014             && memcmp(new.c_cc, settings->main.c_cc, NCCS) == 0)
1015           break;
1016         else
1017           continue;
1018       }
1019
1020 #else
1021 #ifdef HAVE_TERMIO
1022   /* The SYSV-style interface?  */
1023   if (ioctl (fd, waitp ? TCSETAW : TCSETAF, &settings->main) < 0)
1024     return -1;
1025
1026 #else
1027 #ifdef VMS
1028   /* Vehemently Monstrous System?  :-)  */
1029   if (! (SYS$QIOW (0, fd, IO$_SETMODE, &input_iosb, 0, 0,
1030                    &settings->main.class, 12, 0, 0, 0, 0)
1031          & 1))
1032     return -1;
1033
1034 #else
1035 #ifndef MSDOS
1036   /* I give up - I hope you have the BSD ioctls.  */
1037   if (ioctl (fd, (waitp) ? TIOCSETP : TIOCSETN, &settings->main) < 0)
1038     return -1;
1039 #endif /* not MSDOS */
1040
1041 #endif
1042 #endif
1043 #endif
1044
1045   /* Suivant - Do we have to get struct ltchars data?  */
1046 #ifdef HAVE_LTCHARS
1047   if (ioctl (fd, TIOCSLTC, &settings->ltchars) < 0)
1048     return -1;
1049 #endif
1050
1051   /* How about a struct tchars and a wordful of lmode bits?  */
1052 #ifdef HAVE_TCHARS
1053   if (ioctl (fd, TIOCSETC, &settings->tchars) < 0
1054       || ioctl (fd, TIOCLSET, &settings->lmode) < 0)
1055     return -1;
1056 #endif
1057
1058   /* We have survived the tempest.  */
1059   return 0;
1060 }
1061
1062 \f
1063 /* The initial tty mode bits */
1064 struct emacs_tty old_tty;
1065
1066 int term_initted;               /* 1 if outer tty status has been recorded */
1067
1068 #ifdef BSD4_1
1069 /* BSD 4.1 needs to keep track of the lmode bits in order to start
1070    sigio.  */
1071 int lmode;
1072 #endif
1073
1074 #ifndef F_SETOWN_BUG
1075 #ifdef F_SETOWN
1076 int old_fcntl_owner;
1077 #endif /* F_SETOWN */
1078 #endif /* F_SETOWN_BUG */
1079
1080 /* This may also be defined in stdio,
1081    but if so, this does no harm,
1082    and using the same name avoids wasting the other one's space.  */
1083
1084 #if defined (USG) || defined (DGUX)
1085 unsigned char _sobuf[BUFSIZ+8];
1086 #else
1087 char _sobuf[BUFSIZ];
1088 #endif
1089
1090 #ifdef HAVE_LTCHARS
1091 static struct ltchars new_ltchars = {-1,-1,-1,-1,-1,-1};
1092 #endif
1093 #ifdef HAVE_TCHARS
1094   static struct tchars new_tchars = {-1,-1,-1,-1,-1,-1};
1095 #endif
1096
1097 init_sys_modes ()
1098 {
1099   struct emacs_tty tty;
1100
1101 #ifdef VMS
1102 #if 0
1103   static int oob_chars[2] = {0, 1 << 7}; /* catch C-g's */
1104   extern int (*interrupt_signal) ();
1105 #endif
1106 #endif
1107
1108   if (noninteractive)
1109     return;
1110
1111 #ifdef VMS
1112   if (!input_ef)
1113     input_ef = get_kbd_event_flag ();
1114     /* LIB$GET_EF (&input_ef); */
1115   SYS$CLREF (input_ef);
1116   waiting_for_ast = 0;
1117   if (!timer_ef)
1118     timer_ef = get_timer_event_flag ();
1119     /* LIB$GET_EF (&timer_ef); */
1120   SYS$CLREF (timer_ef);
1121 #if 0
1122   if (!process_ef)
1123     {
1124       LIB$GET_EF (&process_ef);
1125       SYS$CLREF (process_ef);
1126     }
1127   if (input_ef / 32 != process_ef / 32)
1128     croak ("Input and process event flags in different clusters.");
1129 #endif
1130   if (input_ef / 32 != timer_ef / 32)
1131     croak ("Input and timer event flags in different clusters.");
1132 #if 0
1133   input_eflist = ((unsigned) 1 << (input_ef % 32)) |
1134     ((unsigned) 1 << (process_ef % 32));
1135 #endif
1136   timer_eflist = ((unsigned) 1 << (input_ef % 32)) |
1137     ((unsigned) 1 << (timer_ef % 32));
1138 #ifndef VMS4_4
1139   sys_access_reinit ();
1140 #endif
1141 #endif /* not VMS */
1142
1143 #ifdef BSD_PGRPS
1144   if (! read_socket_hook && EQ (Vwindow_system, Qnil))
1145     narrow_foreground_group ();
1146 #endif
1147
1148   EMACS_GET_TTY (input_fd, &old_tty);
1149
1150 #ifdef HAVE_X_WINDOWS
1151   /* Emacs' window system on MSDOG uses the `internal terminal' and therefore
1152      needs the initialization code below.  */
1153   if (!read_socket_hook && EQ (Vwindow_system, Qnil))
1154 #endif
1155     {
1156       tty = old_tty;
1157
1158 #if defined (HAVE_TERMIO) || defined (HAVE_TERMIOS)
1159 #ifdef DGUX
1160       /* This allows meta to be sent on 8th bit.  */
1161       tty.main.c_iflag &= ~INPCK;       /* don't check input for parity */
1162 #endif
1163       tty.main.c_iflag |= (IGNBRK);     /* Ignore break condition */
1164       tty.main.c_iflag &= ~ICRNL;       /* Disable map of CR to NL on input */
1165 #ifdef ISTRIP
1166       tty.main.c_iflag &= ~ISTRIP;      /* don't strip 8th bit on input */
1167 #endif
1168       tty.main.c_lflag &= ~ECHO;        /* Disable echo */
1169       tty.main.c_lflag &= ~ICANON;      /* Disable erase/kill processing */
1170 #ifdef IEXTEN
1171       tty.main.c_lflag &= ~IEXTEN;      /* Disable other editing characters.  */
1172 #endif
1173       tty.main.c_lflag |= ISIG; /* Enable signals */
1174       if (flow_control)
1175         {
1176           tty.main.c_iflag |= IXON;     /* Enable start/stop output control */
1177 #ifdef IXANY
1178           tty.main.c_iflag &= ~IXANY;
1179 #endif /* IXANY */
1180         }
1181       else
1182         tty.main.c_iflag &= ~IXON;      /* Disable start/stop output control */
1183       tty.main.c_oflag &= ~ONLCR;       /* Disable map of NL to CR-NL
1184                                            on output */
1185       tty.main.c_oflag &= ~TAB3;        /* Disable tab expansion */
1186 #ifdef CS8
1187       if (meta_key)
1188         {
1189           tty.main.c_cflag |= CS8;      /* allow 8th bit on input */
1190           tty.main.c_cflag &= ~PARENB;/* Don't check parity */
1191         }
1192 #endif
1193       tty.main.c_cc[VINTR] = quit_char; /* C-g (usually) gives SIGINT */
1194       /* Set up C-g for both SIGQUIT and SIGINT.
1195          We don't know which we will get, but we handle both alike
1196          so which one it really gives us does not matter.  */
1197       tty.main.c_cc[VQUIT] = quit_char;
1198       tty.main.c_cc[VMIN] = 1;  /* Input should wait for at least 1 char */
1199       tty.main.c_cc[VTIME] = 0; /* no matter how long that takes.  */
1200 #ifdef VSWTCH
1201       tty.main.c_cc[VSWTCH] = CDISABLE; /* Turn off shell layering use
1202                                            of C-z */
1203 #endif /* VSWTCH */
1204 #if defined (mips) || defined (HAVE_TCATTR)
1205 #ifdef VSUSP
1206       tty.main.c_cc[VSUSP] = CDISABLE;  /* Turn off mips handling of C-z.  */
1207 #endif /* VSUSP */
1208 #ifdef V_DSUSP
1209       tty.main.c_cc[V_DSUSP] = CDISABLE; /* Turn off mips handling of C-y.  */
1210 #endif /* V_DSUSP */
1211 #ifdef VDSUSP /* Some systems have VDSUSP, some have V_DSUSP.  */
1212       tty.main.c_cc[VDSUSP] = CDISABLE;
1213 #endif /* VDSUSP */
1214 #ifdef VLNEXT
1215       tty.main.c_cc[VLNEXT] = CDISABLE;
1216 #endif /* VLNEXT */
1217 #ifdef VREPRINT
1218       tty.main.c_cc[VREPRINT] = CDISABLE;
1219 #endif /* VREPRINT */
1220 #ifdef VWERASE
1221       tty.main.c_cc[VWERASE] = CDISABLE;
1222 #endif /* VWERASE */
1223 #ifdef VDISCARD
1224       tty.main.c_cc[VDISCARD] = CDISABLE;
1225 #endif /* VDISCARD */
1226 #ifdef VSTART
1227       tty.main.c_cc[VSTART] = CDISABLE;
1228 #endif /* VSTART */
1229 #ifdef VSTOP
1230       tty.main.c_cc[VSTOP] = CDISABLE;
1231 #endif /* VSTOP */
1232 #endif /* mips or HAVE_TCATTR */
1233 #ifdef AIX
1234 #ifndef IBMR2AIX
1235       /* AIX enhanced edit loses NULs, so disable it */
1236       tty.main.c_line = 0;
1237       tty.main.c_iflag &= ~ASCEDIT;
1238 #else
1239       tty.main.c_cc[VSTRT] = 255;
1240       tty.main.c_cc[VSTOP] = 255;
1241       tty.main.c_cc[VSUSP] = 255;
1242       tty.main.c_cc[VDSUSP] = 255;
1243 #endif /* IBMR2AIX */
1244       /* Also, PTY overloads NUL and BREAK.
1245          don't ignore break, but don't signal either, so it looks like NUL.
1246          This really serves a purpose only if running in an XTERM window
1247          or via TELNET or the like, but does no harm elsewhere.  */
1248       tty.main.c_iflag &= ~IGNBRK;
1249       tty.main.c_iflag &= ~BRKINT;
1250 #endif
1251 #else /* if not HAVE_TERMIO */
1252 #ifdef VMS
1253       tty.main.tt_char |= TT$M_NOECHO;
1254       if (meta_key)
1255         tty.main.tt_char |= TT$M_EIGHTBIT;
1256       if (flow_control)
1257         tty.main.tt_char |= TT$M_TTSYNC;
1258       else
1259         tty.main.tt_char &= ~TT$M_TTSYNC;
1260       tty.main.tt2_char |= TT2$M_PASTHRU | TT2$M_XON;
1261 #else /* not VMS (BSD, that is) */
1262 #ifndef MSDOS
1263       tty.main.sg_flags &= ~(ECHO | CRMOD | XTABS);
1264       if (meta_key)
1265         tty.main.sg_flags |= ANYP;
1266       tty.main.sg_flags |= interrupt_input ? RAW : CBREAK;
1267 #endif
1268 #endif /* not VMS (BSD, that is) */
1269 #endif /* not HAVE_TERMIO */
1270
1271       /* If going to use CBREAK mode, we must request C-g to interrupt
1272          and turn off start and stop chars, etc.  If not going to use
1273          CBREAK mode, do this anyway so as to turn off local flow
1274          control for user coming over network on 4.2; in this case,
1275          only t_stopc and t_startc really matter.  */
1276 #ifndef HAVE_TERMIO
1277 #ifdef HAVE_TCHARS
1278       /* Note: if not using CBREAK mode, it makes no difference how we
1279          set this */
1280       tty.tchars = new_tchars;
1281       tty.tchars.t_intrc = quit_char;
1282       if (flow_control)
1283         {
1284           tty.tchars.t_startc = '\021';
1285           tty.tchars.t_stopc = '\023';
1286         }
1287
1288       tty.lmode = LDECCTQ | LLITOUT | LPASS8 | LNOFLSH | old_tty.lmode;
1289 #ifdef ultrix
1290       /* Under Ultrix 4.2a, leaving this out doesn't seem to hurt
1291          anything, and leaving it in breaks the meta key.  Go figure.  */
1292       tty.lmode &= ~LLITOUT;
1293 #endif
1294
1295 #ifdef BSD4_1
1296       lmode = tty.lmode;
1297 #endif
1298
1299 #endif /* HAVE_TCHARS */
1300 #endif /* not HAVE_TERMIO */
1301
1302 #ifdef HAVE_LTCHARS
1303       tty.ltchars = new_ltchars;
1304 #endif /* HAVE_LTCHARS */
1305 #ifdef MSDOS    /* Demacs 1.1.2 91/10/20 Manabu Higashida, MW Aug 1993 */
1306       if (!term_initted)
1307         internal_terminal_init ();
1308       dos_ttraw ();
1309 #endif
1310
1311       EMACS_SET_TTY (input_fd, &tty, 0);
1312
1313       /* This code added to insure that, if flow-control is not to be used,
1314          we have an unlocked terminal at the start. */
1315
1316 #ifdef TCXONC
1317       if (!flow_control) ioctl (input_fd, TCXONC, 1);
1318 #endif
1319 #ifndef APOLLO
1320 #ifdef TIOCSTART
1321       if (!flow_control) ioctl (input_fd, TIOCSTART, 0);
1322 #endif
1323 #endif
1324
1325 #ifdef AIX
1326       hft_init ();
1327 #ifdef IBMR2AIX
1328       {
1329         /* IBM's HFT device usually thinks a ^J should be LF/CR.  We need it
1330            to be only LF.  This is the way that is done. */
1331         struct termio tty;
1332
1333         if (ioctl (1, HFTGETID, &tty) != -1)
1334           write (1, "\033[20l", 5);
1335       }
1336 #endif
1337 #endif
1338
1339 #ifdef VMS
1340 /*  Appears to do nothing when in PASTHRU mode.
1341       SYS$QIOW (0, input_fd, IO$_SETMODE|IO$M_OUTBAND, 0, 0, 0,
1342                 interrupt_signal, oob_chars, 0, 0, 0, 0);
1343 */
1344       queue_kbd_input (0);
1345 #endif /* VMS */
1346     }
1347
1348 #ifdef F_SETFL
1349 #ifndef F_SETOWN_BUG
1350 #ifdef F_GETOWN         /* F_SETFL does not imply existence of F_GETOWN */
1351   if (interrupt_input
1352       && ! read_socket_hook && EQ (Vwindow_system, Qnil))
1353     {
1354       old_fcntl_owner = fcntl (input_fd, F_GETOWN, 0);
1355       fcntl (input_fd, F_SETOWN, getpid ());
1356       init_sigio ();
1357     }
1358 #endif /* F_GETOWN */
1359 #endif /* F_SETOWN_BUG */
1360 #endif /* F_SETFL */
1361
1362 #ifdef BSD4_1
1363   if (interrupt_input)
1364     init_sigio ();
1365 #endif
1366
1367 #ifdef VMS  /* VMS sometimes has this symbol but lacks setvbuf.  */
1368 #undef _IOFBF
1369 #endif
1370 #ifdef _IOFBF
1371   /* This symbol is defined on recent USG systems.
1372      Someone says without this call USG won't really buffer the file
1373      even with a call to setbuf. */
1374   setvbuf (stdout, _sobuf, _IOFBF, sizeof _sobuf);
1375 #else
1376   setbuf (stdout, _sobuf);
1377 #endif
1378   if (! read_socket_hook && EQ (Vwindow_system, Qnil))
1379     set_terminal_modes ();
1380
1381   if (term_initted && no_redraw_on_reenter)
1382     {
1383       if (display_completed)
1384         direct_output_forward_char (0);
1385     }
1386   else
1387     {
1388       frame_garbaged = 1;
1389 #ifdef MULTI_FRAME
1390       if (FRAMEP (Vterminal_frame))
1391         FRAME_GARBAGED_P (XFRAME (Vterminal_frame)) = 1;
1392 #endif
1393     }
1394
1395   term_initted = 1;
1396 }
1397
1398 /* Return nonzero if safe to use tabs in output.
1399    At the time this is called, init_sys_modes has not been done yet.  */
1400
1401 tabs_safe_p ()
1402 {
1403   struct emacs_tty tty;
1404
1405   EMACS_GET_TTY (input_fd, &tty);
1406   return EMACS_TTY_TABS_OK (&tty);
1407 }
1408 \f
1409 /* Get terminal size from system.
1410    Store number of lines into *HEIGHTP and width into *WIDTHP.
1411    We store 0 if there's no valid information.  */
1412
1413 get_frame_size (widthp, heightp)
1414      int *widthp, *heightp;
1415 {
1416
1417 #ifdef TIOCGWINSZ
1418
1419   /* BSD-style.  */
1420   struct winsize size;
1421
1422   if (ioctl (input_fd, TIOCGWINSZ, &size) == -1)
1423     *widthp = *heightp = 0;
1424   else
1425     {
1426       *widthp = size.ws_col;
1427       *heightp = size.ws_row;
1428     }
1429
1430 #else
1431 #ifdef TIOCGSIZE
1432
1433   /* SunOS - style.  */
1434   struct ttysize size;
1435
1436   if (ioctl (input_fd, TIOCGSIZE, &size) == -1)
1437     *widthp = *heightp = 0;
1438   else
1439     {
1440       *widthp = size.ts_cols;
1441       *heightp = size.ts_lines;
1442     }
1443
1444 #else
1445 #ifdef VMS
1446
1447   struct sensemode tty;
1448
1449   SYS$QIOW (0, input_fd, IO$_SENSEMODE, &tty, 0, 0,
1450             &tty.class, 12, 0, 0, 0, 0);
1451   *widthp = tty.scr_wid;
1452   *heightp = tty.scr_len;
1453
1454 #else
1455 #ifdef MSDOS
1456   *widthp = ScreenCols ();
1457   *heightp = ScreenRows ();
1458 #else /* system doesn't know size */
1459   *widthp = 0;
1460   *heightp = 0;
1461 #endif
1462
1463 #endif /* not VMS */
1464 #endif /* not SunOS-style */
1465 #endif /* not BSD-style */
1466 }
1467
1468 /* Set the logical window size associated with descriptor FD
1469    to HEIGHT and WIDTH.  This is used mainly with ptys.  */
1470
1471 int
1472 set_window_size (fd, height, width)
1473      int fd, height, width;
1474 {
1475 #ifdef TIOCSWINSZ
1476
1477   /* BSD-style.  */
1478   struct winsize size;
1479   size.ws_row = height;
1480   size.ws_col = width;
1481
1482   if (ioctl (fd, TIOCSWINSZ, &size) == -1)
1483     return 0; /* error */
1484   else
1485     return 1;
1486
1487 #else
1488 #ifdef TIOCSSIZE
1489
1490   /* SunOS - style.  */
1491   struct ttysize size;
1492   size.ts_lines = height;
1493   size.ts_cols = width;
1494
1495   if (ioctl (fd, TIOCGSIZE, &size) == -1)
1496     return 0;
1497   else
1498     return 1;
1499 #else
1500   return -1;
1501 #endif /* not SunOS-style */
1502 #endif /* not BSD-style */
1503 }
1504
1505 \f
1506 /* Prepare the terminal for exiting Emacs; move the cursor to the
1507    bottom of the frame, turn off interrupt-driven I/O, etc.  */
1508 reset_sys_modes ()
1509 {
1510   if (noninteractive)
1511     {
1512       fflush (stdout);
1513       return;
1514     }
1515   if (!term_initted)
1516     return;
1517 #ifdef HAVE_X_WINDOWS
1518   /* Emacs' window system on MSDOG uses the `internal terminal' and therefore
1519      needs the clean-up code below.  */
1520   if (read_socket_hook || !EQ (Vwindow_system, Qnil))
1521     return;
1522 #endif
1523   cursor_to (FRAME_HEIGHT (selected_frame) - 1, 0);
1524 #ifdef MSDOS
1525   if (!EQ (Vwindow_system, Qnil))
1526     {
1527       /* Change to grey on white.  */
1528       putchar ('\e');
1529       putchar ('A');
1530       putchar (7);
1531     }
1532 #endif
1533   clear_end_of_line (FRAME_WIDTH (selected_frame));
1534   /* clear_end_of_line may move the cursor */
1535   cursor_to (FRAME_HEIGHT (selected_frame) - 1, 0);
1536 #ifdef IBMR2AIX
1537   {
1538     /* HFT devices normally use ^J as a LF/CR.  We forced it to
1539        do the LF only.  Now, we need to reset it. */
1540     struct termio tty;
1541
1542     if (ioctl (1, HFTGETID, &tty) != -1)
1543       write (1, "\033[20h", 5);
1544   }
1545 #endif
1546
1547   reset_terminal_modes ();
1548   fflush (stdout);
1549 #ifdef BSD
1550 #ifndef BSD4_1
1551   /* Avoid possible loss of output when changing terminal modes.  */
1552   fsync (fileno (stdout));
1553 #endif
1554 #endif
1555
1556 #ifdef F_SETFL
1557 #ifndef F_SETOWN_BUG
1558 #ifdef F_SETOWN         /* F_SETFL does not imply existence of F_SETOWN */
1559   if (interrupt_input)
1560     {
1561       reset_sigio ();
1562       fcntl (input_fd, F_SETOWN, old_fcntl_owner);
1563     }
1564 #endif /* F_SETOWN */
1565 #endif /* F_SETOWN_BUG */
1566 #ifdef O_NDELAY
1567   fcntl (input_fd, F_SETFL, fcntl (input_fd, F_GETFL, 0) & ~O_NDELAY);
1568 #endif
1569 #endif /* F_SETFL */
1570 #ifdef BSD4_1
1571   if (interrupt_input)
1572     reset_sigio ();
1573 #endif /* BSD4_1 */
1574
1575   while (EMACS_SET_TTY (input_fd, &old_tty, 0) < 0 && errno == EINTR)
1576     ;
1577
1578 #ifdef MSDOS    /* Demacs 1.1.2 91/10/20 Manabu Higashida */
1579   dos_ttcooked ();
1580 #endif
1581
1582 #ifdef AIX
1583   hft_reset ();
1584 #endif
1585
1586 #ifdef BSD_PGRPS
1587   widen_foreground_group ();
1588 #endif
1589 }
1590 \f
1591 #ifdef HAVE_PTYS
1592
1593 /* Set up the proper status flags for use of a pty.  */
1594
1595 setup_pty (fd)
1596      int fd;
1597 {
1598   /* I'm told that TOICREMOTE does not mean control chars
1599      "can't be sent" but rather that they don't have
1600      input-editing or signaling effects.
1601      That should be good, because we have other ways
1602      to do those things in Emacs.
1603      However, telnet mode seems not to work on 4.2.
1604      So TIOCREMOTE is turned off now. */
1605
1606   /* Under hp-ux, if TIOCREMOTE is turned on, some calls
1607      will hang.  In particular, the "timeout" feature (which
1608      causes a read to return if there is no data available)
1609      does this.  Also it is known that telnet mode will hang
1610      in such a way that Emacs must be stopped (perhaps this
1611      is the same problem).
1612
1613      If TIOCREMOTE is turned off, then there is a bug in
1614      hp-ux which sometimes loses data.  Apparently the
1615      code which blocks the master process when the internal
1616      buffer fills up does not work.  Other than this,
1617      though, everything else seems to work fine.
1618
1619      Since the latter lossage is more benign, we may as well
1620      lose that way.  -- cph */
1621 #ifdef FIONBIO
1622 #ifdef SYSV_PTYS
1623   {
1624     int on = 1;
1625     ioctl (fd, FIONBIO, &on);
1626   }
1627 #endif
1628 #endif
1629 #ifdef IBMRTAIX
1630   /* On AIX, the parent gets SIGHUP when a pty attached child dies.  So, we */
1631   /* ignore SIGHUP once we've started a child on a pty.  Note that this may */
1632   /* cause EMACS not to die when it should, i.e., when its own controlling  */
1633   /* tty goes away.  I've complained to the AIX developers, and they may    */
1634   /* change this behavior, but I'm not going to hold my breath.             */
1635   signal (SIGHUP, SIG_IGN);
1636 #endif
1637 }
1638 #endif /* HAVE_PTYS */
1639 \f
1640 #ifdef VMS
1641
1642 /* Assigning an input channel is done at the start of Emacs execution.
1643    This is called each time Emacs is resumed, also, but does nothing
1644    because input_chain is no longer zero.  */
1645
1646 init_vms_input ()
1647 {
1648   int status;
1649
1650   if (input_fd == 0)
1651     {
1652       status = SYS$ASSIGN (&input_dsc, &input_fd, 0, 0);
1653       if (! (status & 1))
1654         LIB$STOP (status);
1655     }
1656 }
1657
1658 /* Deassigning the input channel is done before exiting.  */
1659
1660 stop_vms_input ()
1661 {
1662   return SYS$DASSGN (input_fd);
1663 }
1664
1665 short input_buffer;
1666
1667 /* Request reading one character into the keyboard buffer.
1668    This is done as soon as the buffer becomes empty.  */
1669
1670 queue_kbd_input ()
1671 {
1672   int status;
1673   extern kbd_input_ast ();
1674
1675   waiting_for_ast = 0;
1676   stop_input = 0;
1677   status = SYS$QIO (0, input_fd, IO$_READVBLK,
1678                     &input_iosb, kbd_input_ast, 1,
1679                     &input_buffer, 1, 0, terminator_mask, 0, 0);
1680 }
1681
1682 int input_count;
1683
1684 /* Ast routine that is called when keyboard input comes in
1685    in accord with the SYS$QIO above.  */
1686
1687 kbd_input_ast ()
1688 {
1689   register int c = -1;
1690   int old_errno = errno;
1691   extern EMACS_TIME *input_available_clear_time;
1692
1693   if (waiting_for_ast)
1694     SYS$SETEF (input_ef);
1695   waiting_for_ast = 0;
1696   input_count++;
1697 #ifdef ASTDEBUG
1698   if (input_count == 25)
1699     exit (1);
1700   printf ("Ast # %d,", input_count);
1701   printf (" iosb = %x, %x, %x, %x",
1702           input_iosb.offset, input_iosb.status, input_iosb.termlen,
1703           input_iosb.term);
1704 #endif
1705   if (input_iosb.offset)
1706     {
1707       c = input_buffer;
1708 #ifdef ASTDEBUG
1709       printf (", char = 0%o", c);
1710 #endif
1711     }
1712 #ifdef ASTDEBUG
1713   printf ("\n");
1714   fflush (stdout);
1715   sleep (1);
1716 #endif
1717   if (! stop_input)
1718     queue_kbd_input ();
1719   if (c >= 0)
1720     {
1721       struct input_event e;
1722       e.kind = ascii_keystroke;
1723       XSETINT (e.code, c);
1724       XSETFRAME (e.frame_or_window, selected_frame);
1725       kbd_buffer_store_event (&e);
1726     }
1727   if (input_available_clear_time)
1728     EMACS_SET_SECS_USECS (*input_available_clear_time, 0, 0);
1729   errno = old_errno;
1730 }
1731
1732 /* Wait until there is something in kbd_buffer.  */
1733
1734 wait_for_kbd_input ()
1735 {
1736   extern int have_process_input, process_exited;
1737
1738   /* If already something, avoid doing system calls.  */
1739   if (detect_input_pending ())
1740     {
1741       return;
1742     }
1743   /* Clear a flag, and tell ast routine above to set it.  */
1744   SYS$CLREF (input_ef);
1745   waiting_for_ast = 1;
1746   /* Check for timing error: ast happened while we were doing that.  */
1747   if (!detect_input_pending ())
1748     {
1749       /* No timing error: wait for flag to be set.  */
1750       set_waiting_for_input (0);
1751       SYS$WFLOR (input_ef, input_eflist);
1752       clear_waiting_for_input (0);
1753       if (!detect_input_pending ())
1754         /* Check for subprocess input availability */
1755         {
1756           int dsp = have_process_input || process_exited;
1757
1758           SYS$CLREF (process_ef);
1759           if (have_process_input)
1760             process_command_input ();
1761           if (process_exited)
1762             process_exit ();
1763           if (dsp)
1764             {
1765               update_mode_lines++;
1766               prepare_menu_bars ();
1767               redisplay_preserve_echo_area ();
1768             }
1769         }
1770     }
1771   waiting_for_ast = 0;
1772 }
1773
1774 /* Get rid of any pending QIO, when we are about to suspend
1775    or when we want to throw away pending input.
1776    We wait for a positive sign that the AST routine has run
1777    and therefore there is no I/O request queued when we return.
1778    SYS$SETAST is used to avoid a timing error.  */
1779
1780 end_kbd_input ()
1781 {
1782 #ifdef ASTDEBUG
1783   printf ("At end_kbd_input.\n");
1784   fflush (stdout);
1785   sleep (1);
1786 #endif
1787   if (LIB$AST_IN_PROG ())  /* Don't wait if suspending from kbd_buffer_store_event! */
1788     {
1789       SYS$CANCEL (input_fd);
1790       return;
1791     }
1792
1793   SYS$SETAST (0);
1794   /* Clear a flag, and tell ast routine above to set it.  */
1795   SYS$CLREF (input_ef);
1796   waiting_for_ast = 1;
1797   stop_input = 1;
1798   SYS$CANCEL (input_fd);
1799   SYS$SETAST (1);
1800   SYS$WAITFR (input_ef);
1801   waiting_for_ast = 0;
1802 }
1803
1804 /* Wait for either input available or time interval expiry.  */
1805
1806 input_wait_timeout (timeval)
1807      int timeval;               /* Time to wait, in seconds */
1808 {
1809   int time [2];
1810   static int zero = 0;
1811   static int large = -10000000;
1812
1813   LIB$EMUL (&timeval, &large, &zero, time);       /* Convert to VMS format */
1814
1815   /* If already something, avoid doing system calls.  */
1816   if (detect_input_pending ())
1817     {
1818       return;
1819     }
1820   /* Clear a flag, and tell ast routine above to set it.  */
1821   SYS$CLREF (input_ef);
1822   waiting_for_ast = 1;
1823   /* Check for timing error: ast happened while we were doing that.  */
1824   if (!detect_input_pending ())
1825     {
1826       /* No timing error: wait for flag to be set.  */
1827       SYS$CANTIM (1, 0);
1828       if (SYS$SETIMR (timer_ef, time, 0, 1) & 1) /* Set timer */
1829         SYS$WFLOR (timer_ef, timer_eflist);       /* Wait for timer expiry or input */
1830     }
1831   waiting_for_ast = 0;
1832 }
1833
1834 /* The standard `sleep' routine works some other way
1835    and it stops working if you have ever quit out of it.
1836    This one continues to work.  */
1837
1838 sys_sleep (timeval)
1839      int timeval;
1840 {
1841   int time [2];
1842   static int zero = 0;
1843   static int large = -10000000;
1844
1845   LIB$EMUL (&timeval, &large, &zero, time);       /* Convert to VMS format */
1846
1847   SYS$CANTIM (1, 0);
1848   if (SYS$SETIMR (timer_ef, time, 0, 1) & 1) /* Set timer */
1849     SYS$WAITFR (timer_ef);        /* Wait for timer expiry only */
1850 }
1851
1852 init_sigio ()
1853 {
1854   request_sigio ();
1855 }
1856
1857 reset_sigio ()
1858 {
1859   unrequest_sigio ();
1860 }
1861
1862 request_sigio ()
1863 {
1864   croak ("request sigio");
1865 }
1866
1867 unrequest_sigio ()
1868 {
1869   croak ("unrequest sigio");
1870 }
1871
1872 #endif /* VMS */
1873 \f
1874 /* Note that VMS compiler won't accept defined (CANNOT_DUMP).  */
1875 #ifndef CANNOT_DUMP
1876 #define NEED_STARTS
1877 #endif
1878
1879 #ifndef SYSTEM_MALLOC
1880 #ifndef NEED_STARTS
1881 #define NEED_STARTS
1882 #endif
1883 #endif
1884
1885 #ifdef NEED_STARTS
1886 /* Some systems that cannot dump also cannot implement these.  */
1887
1888 /*
1889  *      Return the address of the start of the text segment prior to
1890  *      doing an unexec.  After unexec the return value is undefined.
1891  *      See crt0.c for further explanation and _start.
1892  *
1893  */
1894
1895 #ifndef HAVE_TEXT_START
1896 char *
1897 start_of_text ()
1898 {
1899 #ifdef TEXT_START
1900   return ((char *) TEXT_START);
1901 #else
1902 #ifdef GOULD
1903   extern csrt ();
1904   return ((char *) csrt);
1905 #else /* not GOULD */
1906   extern int _start ();
1907   return ((char *) _start);
1908 #endif /* GOULD */
1909 #endif /* TEXT_START */
1910 }
1911 #endif /* not HAVE_TEXT_START */
1912
1913 /*
1914  *      Return the address of the start of the data segment prior to
1915  *      doing an unexec.  After unexec the return value is undefined.
1916  *      See crt0.c for further information and definition of data_start.
1917  *
1918  *      Apparently, on BSD systems this is etext at startup.  On
1919  *      USG systems (swapping) this is highly mmu dependent and
1920  *      is also dependent on whether or not the program is running
1921  *      with shared text.  Generally there is a (possibly large)
1922  *      gap between end of text and start of data with shared text.
1923  *
1924  *      On Uniplus+ systems with shared text, data starts at a
1925  *      fixed address.  Each port (from a given oem) is generally
1926  *      different, and the specific value of the start of data can
1927  *      be obtained via the UniPlus+ specific "uvar" system call,
1928  *      however the method outlined in crt0.c seems to be more portable.
1929  *
1930  *      Probably what will have to happen when a USG unexec is available,
1931  *      at least on UniPlus, is temacs will have to be made unshared so
1932  *      that text and data are contiguous.  Then once loadup is complete,
1933  *      unexec will produce a shared executable where the data can be
1934  *      at the normal shared text boundry and the startofdata variable
1935  *      will be patched by unexec to the correct value.
1936  *
1937  */
1938
1939 char *
1940 start_of_data ()
1941 {
1942 #ifdef DATA_START
1943   return ((char *) DATA_START);
1944 #else
1945 #ifdef ORDINARY_LINK
1946   /*
1947    * This is a hack.  Since we're not linking crt0.c or pre_crt0.c,
1948    * data_start isn't defined.  We take the address of environ, which
1949    * is known to live at or near the start of the system crt0.c, and
1950    * we don't sweat the handful of bytes that might lose.
1951    */
1952   extern char **environ;
1953
1954   return((char *) &environ);
1955 #else
1956   extern int data_start;
1957   return ((char *) &data_start);
1958 #endif /* ORDINARY_LINK */
1959 #endif /* DATA_START */
1960 }
1961 #endif /* NEED_STARTS (not CANNOT_DUMP or not SYSTEM_MALLOC) */
1962
1963 #ifndef CANNOT_DUMP
1964 /* Some systems that cannot dump also cannot implement these.  */
1965
1966 /*
1967  *      Return the address of the end of the text segment prior to
1968  *      doing an unexec.  After unexec the return value is undefined.
1969  */
1970
1971 char *
1972 end_of_text ()
1973 {
1974 #ifdef TEXT_END
1975   return ((char *) TEXT_END);
1976 #else
1977   extern int etext;
1978   return ((char *) &etext);
1979 #endif
1980 }
1981
1982 /*
1983  *      Return the address of the end of the data segment prior to
1984  *      doing an unexec.  After unexec the return value is undefined.
1985  */
1986
1987 char *
1988 end_of_data ()
1989 {
1990 #ifdef DATA_END
1991   return ((char *) DATA_END);
1992 #else
1993   extern int edata;
1994   return ((char *) &edata);
1995 #endif
1996 }
1997
1998 #endif /* not CANNOT_DUMP */
1999 \f
2000 /* init_system_name sets up the string for the Lisp function
2001    system-name to return. */
2002
2003 #ifdef BSD4_1
2004 #include <whoami.h>
2005 #endif
2006
2007 extern Lisp_Object Vsystem_name;
2008
2009 #ifndef BSD4_1
2010 #ifndef VMS
2011 #ifdef HAVE_SOCKETS
2012 #include <sys/socket.h>
2013 #include <netdb.h>
2014 #endif /* HAVE_SOCKETS */
2015 #endif /* not VMS */
2016 #endif /* not BSD4_1 */
2017
2018 void
2019 init_system_name ()
2020 {
2021 #ifdef BSD4_1
2022   Vsystem_name = build_string (sysname);
2023 #else
2024 #ifdef VMS
2025   char *sp, *end;
2026   if ((sp = egetenv ("SYS$NODE")) == 0)
2027     Vsystem_name = build_string ("vax-vms");
2028   else if ((end = index (sp, ':')) == 0)
2029     Vsystem_name = build_string (sp);
2030   else
2031     Vsystem_name = make_string (sp, end - sp);
2032 #else
2033 #ifndef HAVE_GETHOSTNAME
2034   struct utsname uts;
2035   uname (&uts);
2036   Vsystem_name = build_string (uts.nodename);
2037 #else /* HAVE_GETHOSTNAME */
2038   int hostname_size = 256;
2039   char *hostname = (char *) alloca (hostname_size);
2040
2041   /* Try to get the host name; if the buffer is too short, try
2042      again.  Apparently, the only indication gethostname gives of
2043      whether the buffer was large enough is the presence or absence
2044      of a '\0' in the string.  Eech.  */
2045   for (;;)
2046     {
2047       gethostname (hostname, hostname_size - 1);
2048       hostname[hostname_size - 1] = '\0';
2049
2050       /* Was the buffer large enough for the '\0'?  */
2051       if (strlen (hostname) < hostname_size - 1)
2052         break;
2053
2054       hostname_size <<= 1;
2055       hostname = (char *) alloca (hostname_size);
2056     }
2057 #ifdef HAVE_SOCKETS
2058   /* Turn the hostname into the official, fully-qualified hostname.
2059      Don't do this if we're going to dump; this can confuse system
2060      libraries on some machines and make the dumped emacs core dump. */
2061 #ifndef CANNOT_DUMP
2062   if (initialized)
2063 #endif /* not CANNOT_DUMP */
2064     {
2065       struct hostent *hp;
2066       int count;
2067       for (count = 0; count < 10; count++)
2068         {
2069 #ifdef TRY_AGAIN
2070           h_errno = 0;
2071 #endif
2072           hp = gethostbyname (hostname);
2073 #ifdef TRY_AGAIN
2074           if (! (hp == 0 && h_errno == TRY_AGAIN))
2075 #endif
2076             break;
2077           Fsleep_for (make_number (1), Qnil);
2078         }
2079       if (hp)
2080         {
2081           char *fqdn = hp->h_name;
2082           char *p;
2083
2084           if (!index (fqdn, '.'))
2085             {
2086               /* We still don't have a fully qualified domain name.
2087                  Try to find one in the list of alternate names */
2088               char **alias = hp->h_aliases;
2089               while (*alias && !index (*alias, '.'))
2090                 alias++;
2091               if (*alias)
2092                 fqdn = *alias;
2093             }
2094           hostname = fqdn;
2095 #if 0
2096           /* Convert the host name to lower case.  */
2097           /* Using ctype.h here would introduce a possible locale
2098              dependence that is probably wrong for hostnames.  */
2099           p = hostname;
2100           while (*p)
2101             {
2102               if (*p >= 'A' && *p <= 'Z')
2103                 *p += 'a' - 'A';
2104               p++;
2105             }
2106 #endif
2107         }
2108     }
2109 #endif /* HAVE_SOCKETS */
2110   Vsystem_name = build_string (hostname);
2111 #endif /* HAVE_GETHOSTNAME */
2112 #endif /* VMS */
2113 #endif /* BSD4_1 */
2114   {
2115     unsigned char *p;
2116     for (p = XSTRING (Vsystem_name)->data; *p; p++)
2117       if (*p == ' ' || *p == '\t')
2118         *p = '-';
2119   }
2120 }
2121 \f
2122 #ifndef VMS
2123 #ifndef HAVE_SELECT
2124
2125 #ifdef HAVE_X_WINDOWS
2126 /* Cause explanatory error message at compile time,
2127    since the select emulation is not good enough for X.  */
2128 int *x = &x_windows_lose_if_no_select_system_call;
2129 #endif
2130
2131 /* Emulate as much as select as is possible under 4.1 and needed by Gnu Emacs
2132  * Only checks read descriptors.
2133  */
2134 /* How long to wait between checking fds in select */
2135 #define SELECT_PAUSE 1
2136 int select_alarmed;
2137
2138 /* For longjmp'ing back to read_input_waiting.  */
2139
2140 jmp_buf read_alarm_throw;
2141
2142 /* Nonzero if the alarm signal should throw back to read_input_waiting.
2143    The read_socket_hook function sets this to 1 while it is waiting.  */
2144
2145 int read_alarm_should_throw;
2146
2147 SIGTYPE
2148 select_alarm ()
2149 {
2150   select_alarmed = 1;
2151 #ifdef BSD4_1
2152   sigrelse (SIGALRM);
2153 #else /* not BSD4_1 */
2154   signal (SIGALRM, SIG_IGN);
2155 #endif /* not BSD4_1 */
2156   if (read_alarm_should_throw)
2157     longjmp (read_alarm_throw, 1);
2158 }
2159
2160 /* Only rfds are checked.  */
2161 int
2162 select (nfds, rfds, wfds, efds, timeout)
2163      int nfds;
2164      int *rfds, *wfds, *efds, *timeout;
2165 {
2166   int ravail = 0, orfds = 0, old_alarm;
2167   int timeoutval = timeout ? *timeout : 100000;
2168   int *local_timeout = &timeoutval;
2169   extern int proc_buffered_char[];
2170 #ifndef subprocesses
2171   int process_tick = 0, update_tick = 0;
2172 #else
2173   extern int process_tick, update_tick;
2174 #endif
2175   SIGTYPE (*old_trap) ();
2176   unsigned char buf;
2177
2178   if (rfds)
2179     {
2180       orfds = *rfds;
2181       *rfds = 0;
2182     }
2183   if (wfds)
2184     *wfds = 0;
2185   if (efds)
2186     *efds = 0;
2187
2188   /* If we are looking only for the terminal, with no timeout,
2189      just read it and wait -- that's more efficient.  */
2190   if (orfds == 1 && *local_timeout == 100000 && process_tick == update_tick)
2191     {
2192       if (! detect_input_pending ())
2193         read_input_waiting ();
2194       *rfds = 1;
2195       return 1;
2196     }
2197
2198   /* Once a second, till the timer expires, check all the flagged read
2199    * descriptors to see if any input is available.  If there is some then
2200    * set the corresponding bit in the return copy of rfds.
2201    */
2202   while (1)
2203     {
2204       register int to_check, bit, fd;
2205
2206       if (rfds)
2207         {
2208           for (to_check = nfds, bit = 1, fd = 0; --to_check >= 0; bit <<= 1, fd++)
2209             {
2210               if (orfds & bit)
2211                 {
2212                   int avail = 0, status = 0;
2213
2214                   if (bit == 1)
2215                     avail = detect_input_pending (); /* Special keyboard handler */
2216                   else
2217                     {
2218 #ifdef FIONREAD
2219                       status = ioctl (fd, FIONREAD, &avail);
2220 #else /* no FIONREAD */
2221 #ifdef MSDOS
2222                       abort (); /* I don't think we need it.  */
2223 #else /* not MSDOS */
2224                       /* Hoping it will return -1 if nothing available
2225                          or 0 if all 0 chars requested are read.  */
2226                       if (proc_buffered_char[fd] >= 0)
2227                         avail = 1;
2228                       else
2229                         {
2230                           avail = read (fd, &buf, 1);
2231                           if (avail > 0)
2232                             proc_buffered_char[fd] = buf;
2233                         }
2234 #endif /* not MSDOS */
2235 #endif /* no FIONREAD */
2236                     }
2237                   if (status >= 0 && avail > 0)
2238                     {
2239                       (*rfds) |= bit;
2240                       ravail++;
2241                     }
2242                 }
2243             }
2244         }
2245       if (*local_timeout == 0 || ravail != 0 || process_tick != update_tick)
2246         break;
2247       old_alarm = alarm (0);
2248       old_trap = signal (SIGALRM, select_alarm);
2249       select_alarmed = 0;
2250       alarm (SELECT_PAUSE);
2251       /* Wait for a SIGALRM (or maybe a SIGTINT) */
2252       while (select_alarmed == 0 && *local_timeout != 0
2253              && process_tick == update_tick)
2254         {
2255 #ifdef MSDOS
2256           sleep_or_kbd_hit (SELECT_PAUSE, (orfds & 1) != 0);
2257           select_alarm ();
2258 #else /* not MSDOS */
2259           /* If we are interested in terminal input,
2260              wait by reading the terminal.
2261              That makes instant wakeup for terminal input at least.  */
2262           if (orfds & 1)
2263             {
2264               read_input_waiting ();
2265               if (detect_input_pending ())
2266                 select_alarmed = 1;
2267             }
2268           else
2269             pause ();
2270 #endif /* not MSDOS */
2271         }
2272       (*local_timeout) -= SELECT_PAUSE;
2273       /* Reset the old alarm if there was one */
2274       alarm (0);
2275       signal (SIGALRM, old_trap);
2276       if (old_alarm != 0)
2277         {
2278           /* Reset or forge an interrupt for the original handler. */
2279           old_alarm -= SELECT_PAUSE;
2280           if (old_alarm <= 0)
2281             kill (getpid (), SIGALRM); /* Fake an alarm with the orig' handler */
2282           else
2283             alarm (old_alarm);
2284         }
2285       if (*local_timeout == 0)  /* Stop on timer being cleared */
2286         break;
2287     }
2288   return ravail;
2289 }
2290
2291 /* Read keyboard input into the standard buffer,
2292    waiting for at least one character.  */
2293
2294 /* Make all keyboard buffers much bigger when using X windows.  */
2295 #ifdef HAVE_X_WINDOWS
2296 #define BUFFER_SIZE_FACTOR 16
2297 #else
2298 #define BUFFER_SIZE_FACTOR 1
2299 #endif
2300
2301 read_input_waiting ()
2302 {
2303   struct input_event e;
2304   int nread, i;
2305   extern int quit_char;
2306
2307   if (read_socket_hook)
2308     {
2309       struct input_event buf[256];
2310
2311       read_alarm_should_throw = 0;
2312       if (! setjmp (read_alarm_throw))
2313         nread = (*read_socket_hook) (0, buf, 256, 1, 0);
2314       else
2315         nread = -1;
2316
2317       /* Scan the chars for C-g and store them in kbd_buffer.  */
2318       for (i = 0; i < nread; i++)
2319         {
2320           kbd_buffer_store_event (&buf[i]);
2321           /* Don't look at input that follows a C-g too closely.
2322              This reduces lossage due to autorepeat on C-g.  */
2323           if (buf[i].kind == ascii_keystroke
2324               && XINT(buf[i].code) == quit_char)
2325             break;
2326         }
2327     }
2328   else
2329     {
2330       char buf[3];
2331       nread = read (fileno (stdin), buf, 1);
2332
2333       /* Scan the chars for C-g and store them in kbd_buffer.  */
2334       e.kind = ascii_keystroke;
2335       XSETFRAME (e.frame_or_window, selected_frame);
2336       e.modifiers = 0;
2337       for (i = 0; i < nread; i++)
2338         {
2339           /* Convert chars > 0177 to meta events if desired.
2340              We do this under the same conditions that read_avail_input does.  */
2341           if (read_socket_hook == 0)
2342             {
2343               /* If the user says she has a meta key, then believe her. */
2344               if (meta_key == 1 && (buf[i] & 0x80))
2345                 e.modifiers = meta_modifier;
2346               if (meta_key != 2)
2347                 buf[i] &= ~0x80;
2348             }
2349
2350           XSETINT (e.code, buf[i]);
2351           kbd_buffer_store_event (&e);
2352           /* Don't look at input that follows a C-g too closely.
2353              This reduces lossage due to autorepeat on C-g.  */
2354           if (buf[i] == quit_char)
2355             break;
2356         }
2357     }
2358 }
2359
2360 #endif /* not HAVE_SELECT */
2361 #endif /* not VMS */
2362 \f
2363 #ifdef BSD4_1
2364 /*
2365  * Partially emulate 4.2 open call.
2366  * open is defined as this in 4.1.
2367  *
2368  * - added by Michael Bloom @ Citicorp/TTI
2369  *
2370  */
2371
2372 int
2373 sys_open (path, oflag, mode)
2374      char *path;
2375      int oflag, mode;
2376 {
2377   if (oflag & O_CREAT)
2378     return creat (path, mode);
2379   else
2380     return open (path, oflag);
2381 }
2382
2383 init_sigio ()
2384 {
2385   if (noninteractive)
2386     return;
2387   lmode = LINTRUP | lmode;
2388   ioctl (0, TIOCLSET, &lmode);
2389 }
2390
2391 reset_sigio ()
2392 {
2393   if (noninteractive)
2394     return;
2395   lmode = ~LINTRUP & lmode;
2396   ioctl (0, TIOCLSET, &lmode);
2397 }
2398
2399 request_sigio ()
2400 {
2401   sigrelse (SIGTINT);
2402
2403   interrupts_deferred = 0;
2404 }
2405
2406 unrequest_sigio ()
2407 {
2408   sighold (SIGTINT);
2409
2410   interrupts_deferred = 1;
2411 }
2412
2413 /* still inside #ifdef BSD4_1 */
2414 #ifdef subprocesses
2415
2416 int sigheld; /* Mask of held signals */
2417
2418 sigholdx (signum)
2419      int signum;
2420 {
2421   sigheld |= sigbit (signum);
2422   sighold (signum);
2423 }
2424
2425 sigisheld (signum)
2426      int signum;
2427 {
2428   sigheld |= sigbit (signum);
2429 }
2430
2431 sigunhold (signum)
2432      int signum;
2433 {
2434   sigheld &= ~sigbit (signum);
2435   sigrelse (signum);
2436 }
2437
2438 sigfree ()    /* Free all held signals */
2439 {
2440   int i;
2441   for (i = 0; i < NSIG; i++)
2442     if (sigheld & sigbit (i))
2443       sigrelse (i);
2444   sigheld = 0;
2445 }
2446
2447 sigbit (i)
2448 {
2449   return 1 << (i - 1);
2450 }
2451 #endif /* subprocesses */
2452 #endif /* BSD4_1 */
2453 \f
2454 /* POSIX signals support - DJB */
2455 /* Anyone with POSIX signals should have ANSI C declarations */
2456
2457 #ifdef POSIX_SIGNALS
2458
2459 sigset_t old_mask, empty_mask, full_mask, temp_mask;
2460 static struct sigaction new_action, old_action;
2461
2462 init_signals ()
2463 {
2464   sigemptyset (&empty_mask);
2465   sigfillset (&full_mask);
2466 }
2467
2468 signal_handler_t
2469 sys_signal (int signal_number, signal_handler_t action)
2470 {
2471 #ifdef DGUX
2472   /* This gets us restartable system calls for efficiency.
2473      The "else" code will works as well. */
2474   return (berk_signal (signal_number, action));
2475 #else
2476   sigemptyset (&new_action.sa_mask);
2477   new_action.sa_handler = action;
2478 #ifdef SA_RESTART
2479   /* Emacs mostly works better with restartable system services. If this
2480    * flag exists, we probably want to turn it on here.
2481    */
2482   new_action.sa_flags = SA_RESTART;
2483 #else
2484   new_action.sa_flags = 0;
2485 #endif
2486   sigaction (signal_number, &new_action, &old_action);
2487   return (old_action.sa_handler);
2488 #endif /* DGUX */
2489 }
2490
2491 #ifndef __GNUC__
2492 /* If we're compiling with GCC, we don't need this function, since it
2493    can be written as a macro.  */
2494 sigset_t
2495 sys_sigmask (int sig)
2496 {
2497   sigset_t mask;
2498   sigemptyset (&mask);
2499   sigaddset (&mask, sig);
2500   return mask;
2501 }
2502 #endif
2503
2504 int
2505 sys_sigpause (sigset_t new_mask)
2506 {
2507   /* pause emulating berk sigpause... */
2508   sigsuspend (&new_mask);
2509   return (EINTR);
2510 }
2511
2512 /* I'd like to have these guys return pointers to the mask storage in here,
2513    but there'd be trouble if the code was saving multiple masks.  I'll be
2514    safe and pass the structure.  It normally won't be more than 2 bytes
2515    anyhow. - DJB */
2516
2517 sigset_t
2518 sys_sigblock (sigset_t new_mask)
2519 {
2520   sigset_t old_mask;
2521   sigprocmask (SIG_BLOCK, &new_mask, &old_mask);
2522   return (old_mask);
2523 }
2524
2525 sigset_t
2526 sys_sigunblock (sigset_t new_mask)
2527 {
2528   sigset_t old_mask;
2529   sigprocmask (SIG_UNBLOCK, &new_mask, &old_mask);
2530   return (old_mask);
2531 }
2532
2533 sigset_t
2534 sys_sigsetmask (sigset_t new_mask)
2535 {
2536   sigset_t old_mask;
2537   sigprocmask (SIG_SETMASK, &new_mask, &old_mask);
2538   return (old_mask);
2539 }
2540
2541 #endif /* POSIX_SIGNALS */
2542 \f
2543 #ifndef BSTRING
2544
2545 #ifndef bzero
2546
2547 void
2548 bzero (b, length)
2549      register char *b;
2550      register int length;
2551 {
2552 #ifdef VMS
2553   short zero = 0;
2554   long max_str = 65535;
2555
2556   while (length > max_str) {
2557     (void) LIB$MOVC5 (&zero, &zero, &zero, &max_str, b);
2558     length -= max_str;
2559     b += max_str;
2560   }
2561   max_str = length;
2562   (void) LIB$MOVC5 (&zero, &zero, &zero, &max_str, b);
2563 #else
2564   while (length-- > 0)
2565     *b++ = 0;
2566 #endif /* not VMS */
2567 }
2568
2569 #endif /* no bzero */
2570
2571 #ifndef bcopy
2572 /* Saying `void' requires a declaration, above, where bcopy is used
2573    and that declaration causes pain for systems where bcopy is a macro.  */
2574 bcopy (b1, b2, length)
2575      register char *b1;
2576      register char *b2;
2577      register int length;
2578 {
2579 #ifdef VMS
2580   long max_str = 65535;
2581
2582   while (length > max_str) {
2583     (void) LIB$MOVC3 (&max_str, b1, b2);
2584     length -= max_str;
2585     b1 += max_str;
2586     b2 += max_str;
2587   }
2588   max_str = length;
2589   (void) LIB$MOVC3 (&length, b1, b2);
2590 #else
2591   while (length-- > 0)
2592     *b2++ = *b1++;
2593 #endif /* not VMS */
2594 }
2595 #endif /* no bcopy */
2596
2597 #ifndef bcmp
2598 int
2599 bcmp (b1, b2, length)   /* This could be a macro! */
2600      register char *b1;
2601      register char *b2;
2602      register int length;
2603 {
2604 #ifdef VMS
2605   struct dsc$descriptor_s src1 = {length, DSC$K_DTYPE_T, DSC$K_CLASS_S, b1};
2606   struct dsc$descriptor_s src2 = {length, DSC$K_DTYPE_T, DSC$K_CLASS_S, b2};
2607
2608   return STR$COMPARE (&src1, &src2);
2609 #else
2610   while (length-- > 0)
2611     if (*b1++ != *b2++)
2612       return 1;
2613
2614   return 0;
2615 #endif /* not VMS */
2616 }
2617 #endif /* no bcmp */
2618
2619 #endif /* not BSTRING */
2620 \f
2621 #ifndef HAVE_RANDOM
2622 #ifndef random
2623
2624 /*
2625  *      The BSD random returns numbers in the range of
2626  *      0 to 2e31 - 1.  The USG rand returns numbers in the
2627  *      range of 0 to 2e15 - 1.  This is probably not significant
2628  *      in this usage.
2629  */
2630
2631 long
2632 random ()
2633 {
2634 #ifdef HAVE_LRAND48
2635   return lrand48 ();
2636 #else
2637 /* The BSD rand returns numbers in the range of 0 to 2e31 - 1,
2638    with unusable least significant bits.  The USG rand returns
2639    numbers in the range of 0 to 2e15 - 1, all usable.  Let us
2640    build a usable 30 bit number from either.  */
2641 #ifdef USG
2642   return (rand () << 15) + rand ();
2643 #else
2644   return (rand () & 0x3fff8000) + (rand () >> 16);
2645 #endif
2646 #endif
2647 }
2648
2649 srandom (arg)
2650      int arg;
2651 {
2652 #ifdef HAVE_LRAND48
2653   srand48 (arg);
2654 #else
2655   srand (arg);
2656 #endif
2657 }
2658
2659 #endif /* no random */
2660 #endif /* not HAVE_RANDOM */
2661 \f
2662 #ifdef WRONG_NAME_INSQUE
2663
2664 insque (q,p)
2665      caddr_t q,p;
2666 {
2667   _insque (q,p);
2668 }
2669
2670 #endif
2671 \f
2672 #ifdef VMS
2673
2674 #ifdef getenv
2675 /* If any place else asks for the TERM variable,
2676    allow it to be overridden with the EMACS_TERM variable
2677    before attempting to translate the logical name TERM.  As a last
2678    resort, ask for VAX C's special idea of the TERM variable.  */
2679 #undef getenv
2680 char *
2681 sys_getenv (name)
2682      char *name;
2683 {
2684   register char *val;
2685   static char buf[256];
2686   static struct dsc$descriptor_s equiv
2687     = {sizeof (buf), DSC$K_DTYPE_T, DSC$K_CLASS_S, buf};
2688   static struct dsc$descriptor_s d_name
2689     = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0};
2690   short eqlen;
2691
2692   if (!strcmp (name, "TERM"))
2693     {
2694       val = (char *) getenv ("EMACS_TERM");
2695       if (val)
2696         return val;
2697     }
2698
2699   d_name.dsc$w_length = strlen (name);
2700   d_name.dsc$a_pointer = name;
2701   if (LIB$SYS_TRNLOG (&d_name, &eqlen, &equiv) == 1)
2702     {
2703       char *str = (char *) xmalloc (eqlen + 1);
2704       bcopy (buf, str, eqlen);
2705       str[eqlen] = '\0';
2706       /* This is a storage leak, but a pain to fix.  With luck,
2707          no one will ever notice.  */
2708       return str;
2709     }
2710   return (char *) getenv (name);
2711 }
2712 #endif /* getenv */
2713
2714 #ifdef abort
2715 /* Since VMS doesn't believe in core dumps, the only way to debug this beast is
2716    to force a call on the debugger from within the image. */
2717 #undef abort
2718 sys_abort ()
2719 {
2720   reset_sys_modes ();
2721   LIB$SIGNAL (SS$_DEBUG);
2722 }
2723 #endif /* abort */
2724 #endif /* VMS */
2725 \f
2726 #ifdef VMS
2727 #ifdef LINK_CRTL_SHARE
2728 #ifdef SHAREABLE_LIB_BUG
2729 /* Variables declared noshare and initialized in sharable libraries
2730    cannot be shared.  The VMS linker incorrectly forces you to use a private
2731    version which is uninitialized... If not for this "feature", we
2732    could use the C library definition of sys_nerr and sys_errlist. */
2733 int sys_nerr = 35;
2734 char *sys_errlist[] =
2735   {
2736     "error 0",
2737     "not owner",
2738     "no such file or directory",
2739     "no such process",
2740     "interrupted system call",
2741     "i/o error",
2742     "no such device or address",
2743     "argument list too long",
2744     "exec format error",
2745     "bad file number",
2746     "no child process",
2747     "no more processes",
2748     "not enough memory",
2749     "permission denied",
2750     "bad address",
2751     "block device required",
2752     "mount devices busy",
2753     "file exists",
2754     "cross-device link",
2755     "no such device",
2756     "not a directory",
2757     "is a directory",
2758     "invalid argument",
2759     "file table overflow",
2760     "too many open files",
2761     "not a typewriter",
2762     "text file busy",
2763     "file too big",
2764     "no space left on device",
2765     "illegal seek",
2766     "read-only file system",
2767     "too many links",
2768     "broken pipe",
2769     "math argument",
2770     "result too large",
2771     "I/O stream empty",
2772     "vax/vms specific error code nontranslatable error"
2773   };
2774 #endif /* SHAREABLE_LIB_BUG */
2775 #endif /* LINK_CRTL_SHARE */
2776 #endif /* VMS */
2777
2778 #ifndef HAVE_STRERROR
2779 char *
2780 strerror (errnum)
2781      int errnum;
2782 {
2783   extern char *sys_errlist[];
2784   extern int sys_nerr;
2785
2786   if (errnum >= 0 && errnum < sys_nerr)
2787     return sys_errlist[errnum];
2788   return (char *) "Unknown error";
2789 }
2790
2791 #endif /* ! HAVE_STRERROR */
2792 \f
2793 #ifdef INTERRUPTIBLE_OPEN
2794
2795 int
2796 /* VARARGS 2 */
2797 sys_open (path, oflag, mode)
2798      char *path;
2799      int oflag, mode;
2800 {
2801   register int rtnval;
2802
2803   while ((rtnval = open (path, oflag, mode)) == -1
2804          && (errno == EINTR));
2805   return (rtnval);
2806 }
2807
2808 #endif /* INTERRUPTIBLE_OPEN */
2809
2810 #ifdef INTERRUPTIBLE_CLOSE
2811
2812 sys_close (fd)
2813      int fd;
2814 {
2815   register int rtnval;
2816
2817   while ((rtnval = close (fd)) == -1
2818          && (errno == EINTR));
2819   return rtnval;
2820 }
2821
2822 #endif /* INTERRUPTIBLE_CLOSE */
2823
2824 #ifdef INTERRUPTIBLE_IO
2825
2826 int
2827 sys_read (fildes, buf, nbyte)
2828      int fildes;
2829      char *buf;
2830      unsigned int nbyte;
2831 {
2832   register int rtnval;
2833
2834   while ((rtnval = read (fildes, buf, nbyte)) == -1
2835          && (errno == EINTR));
2836   return (rtnval);
2837 }
2838
2839 int
2840 sys_write (fildes, buf, nbyte)
2841      int fildes;
2842      char *buf;
2843      unsigned int nbyte;
2844 {
2845   register int rtnval, bytes_written;
2846
2847   bytes_written = 0;
2848
2849   while (nbyte > 0)
2850     {
2851       rtnval = write (fildes, buf, nbyte);
2852
2853       if (rtnval == -1)
2854         {
2855           if (errno == EINTR)
2856             continue;
2857           else
2858             return (bytes_written ? bytes_written : -1);
2859         }
2860
2861       buf += rtnval;
2862       nbyte -= rtnval;
2863       bytes_written += rtnval;
2864     }
2865   return (bytes_written);
2866 }
2867
2868 #endif /* INTERRUPTIBLE_IO */
2869 \f
2870 #ifndef HAVE_VFORK
2871
2872 /*
2873  *      Substitute fork for vfork on USG flavors.
2874  */
2875
2876 vfork ()
2877 {
2878   return (fork ());
2879 }
2880
2881 #endif /* not HAVE_VFORK */
2882 \f
2883 #ifdef USG
2884 /*
2885  *      All of the following are for USG.
2886  *
2887  *      On USG systems the system calls are INTERRUPTIBLE by signals
2888  *      that the user program has elected to catch.  Thus the system call
2889  *      must be retried in these cases.  To handle this without massive
2890  *      changes in the source code, we remap the standard system call names
2891  *      to names for our own functions in sysdep.c that do the system call
2892  *      with retries.  Actually, for portability reasons, it is good
2893  *      programming practice, as this example shows, to limit all actual
2894  *      system calls to a single occurrence in the source.  Sure, this
2895  *      adds an extra level of function call overhead but it is almost
2896  *      always negligible.   Fred Fish, Unisoft Systems Inc.
2897  */
2898
2899 #ifndef HAVE_SYS_SIGLIST
2900 char *sys_siglist[NSIG + 1] =
2901 {
2902 #ifdef AIX
2903 /* AIX has changed the signals a bit */
2904   "bogus signal",                       /* 0 */
2905   "hangup",                             /* 1  SIGHUP */
2906   "interrupt",                          /* 2  SIGINT */
2907   "quit",                               /* 3  SIGQUIT */
2908   "illegal instruction",                /* 4  SIGILL */
2909   "trace trap",                         /* 5  SIGTRAP */
2910   "IOT instruction",                    /* 6  SIGIOT */
2911   "crash likely",                       /* 7  SIGDANGER */
2912   "floating point exception",           /* 8  SIGFPE */
2913   "kill",                               /* 9  SIGKILL */
2914   "bus error",                          /* 10 SIGBUS */
2915   "segmentation violation",             /* 11 SIGSEGV */
2916   "bad argument to system call",        /* 12 SIGSYS */
2917   "write on a pipe with no one to read it", /* 13 SIGPIPE */
2918   "alarm clock",                        /* 14 SIGALRM */
2919   "software termination signum",        /* 15 SIGTERM */
2920   "user defined signal 1",              /* 16 SIGUSR1 */
2921   "user defined signal 2",              /* 17 SIGUSR2 */
2922   "death of a child",                   /* 18 SIGCLD */
2923   "power-fail restart",                 /* 19 SIGPWR */
2924   "bogus signal",                       /* 20 */
2925   "bogus signal",                       /* 21 */
2926   "bogus signal",                       /* 22 */
2927   "bogus signal",                       /* 23 */
2928   "bogus signal",                       /* 24 */
2929   "LAN I/O interrupt",                  /* 25 SIGAIO */
2930   "PTY I/O interrupt",                  /* 26 SIGPTY */
2931   "I/O intervention required",          /* 27 SIGIOINT */
2932   "HFT grant",                          /* 28 SIGGRANT */
2933   "HFT retract",                        /* 29 SIGRETRACT */
2934   "HFT sound done",                     /* 30 SIGSOUND */
2935   "HFT input ready",                    /* 31 SIGMSG */
2936 #else /* not AIX */
2937   "bogus signal",                       /* 0 */
2938   "hangup",                             /* 1  SIGHUP */
2939   "interrupt",                          /* 2  SIGINT */
2940   "quit",                               /* 3  SIGQUIT */
2941   "illegal instruction",                /* 4  SIGILL */
2942   "trace trap",                         /* 5  SIGTRAP */
2943   "IOT instruction",                    /* 6  SIGIOT */
2944   "EMT instruction",                    /* 7  SIGEMT */
2945   "floating point exception",           /* 8  SIGFPE */
2946   "kill",                               /* 9  SIGKILL */
2947   "bus error",                          /* 10 SIGBUS */
2948   "segmentation violation",             /* 11 SIGSEGV */
2949   "bad argument to system call",        /* 12 SIGSYS */
2950   "write on a pipe with no one to read it", /* 13 SIGPIPE */
2951   "alarm clock",                        /* 14 SIGALRM */
2952   "software termination signum",        /* 15 SIGTERM */
2953   "user defined signal 1",              /* 16 SIGUSR1 */
2954   "user defined signal 2",              /* 17 SIGUSR2 */
2955   "death of a child",                   /* 18 SIGCLD */
2956   "power-fail restart",                 /* 19 SIGPWR */
2957 #ifdef sun
2958   "window size change",                     /* 20 SIGWINCH */
2959   "urgent socket condition",                /* 21 SIGURG */
2960   "pollable event occured",                 /* 22 SIGPOLL */
2961   "stop (cannot be caught or ignored)", /*  23 SIGSTOP */
2962   "user stop requested from tty",           /* 24 SIGTSTP */
2963   "stopped process has been continued", /* 25 SIGCONT */
2964   "background tty read attempted",          /* 26 SIGTTIN */
2965   "background tty write attempted",    /* 27 SIGTTOU */
2966   "virtual timer expired",                  /* 28 SIGVTALRM */
2967   "profiling timer expired",                /* 29 SIGPROF */
2968   "exceeded cpu limit",                     /* 30 SIGXCPU */
2969   "exceeded file size limit",               /* 31 SIGXFSZ */
2970   "process's lwps are blocked",     /*  32 SIGWAITING */
2971   "special signal used by thread library", /* 33 SIGLWP */
2972 #ifdef SIGFREEZE
2973   "Special Signal Used By CPR",     /* 34 SIGFREEZE */
2974 #endif
2975 #ifdef SIGTHAW
2976   "Special Signal Used By CPR",     /* 35 SIGTHAW */
2977 #endif
2978 #endif /* sun */
2979 #endif /* not AIX */
2980   0
2981   };
2982 #endif /* HAVE_SYS_SIGLIST */
2983
2984 /*
2985  *      Warning, this function may not duplicate 4.2 action properly
2986  *      under error conditions.
2987  */
2988
2989 #ifndef MAXPATHLEN
2990 /* In 4.1, param.h fails to define this.  */
2991 #define MAXPATHLEN 1024
2992 #endif
2993
2994 #ifndef HAVE_GETWD
2995
2996 char *
2997 getwd (pathname)
2998      char *pathname;
2999 {
3000   char *npath, *spath;
3001   extern char *getcwd ();
3002
3003   BLOCK_INPUT;                  /* getcwd uses malloc */
3004   spath = npath = getcwd ((char *) 0, MAXPATHLEN);
3005   if (spath == 0)
3006     return spath;
3007   /* On Altos 3068, getcwd can return @hostname/dir, so discard
3008      up to first slash.  Should be harmless on other systems.  */
3009   while (*npath && *npath != '/')
3010     npath++;
3011   strcpy (pathname, npath);
3012   free (spath);                 /* getcwd uses malloc */
3013   UNBLOCK_INPUT;
3014   return pathname;
3015 }
3016
3017 #endif /* HAVE_GETWD */
3018
3019 /*
3020  *      Emulate rename using unlink/link.  Note that this is
3021  *      only partially correct.  Also, doesn't enforce restriction
3022  *      that files be of same type (regular->regular, dir->dir, etc).
3023  */
3024
3025 #ifndef HAVE_RENAME
3026
3027 rename (from, to)
3028      const char *from;
3029      const char *to;
3030 {
3031   if (access (from, 0) == 0)
3032     {
3033       unlink (to);
3034       if (link (from, to) == 0)
3035         if (unlink (from) == 0)
3036           return (0);
3037     }
3038   return (-1);
3039 }
3040
3041 #endif
3042
3043
3044 #ifdef HPUX
3045 #ifndef HAVE_PERROR
3046
3047 /* HPUX curses library references perror, but as far as we know
3048    it won't be called.  Anyway this definition will do for now.  */
3049
3050 perror ()
3051 {
3052 }
3053
3054 #endif /* not HAVE_PERROR */
3055 #endif /* HPUX */
3056
3057 #ifndef HAVE_DUP2
3058
3059 /*
3060  *      Emulate BSD dup2.  First close newd if it already exists.
3061  *      Then, attempt to dup oldd.  If not successful, call dup2 recursively
3062  *      until we are, then close the unsuccessful ones.
3063  */
3064
3065 dup2 (oldd, newd)
3066      int oldd;
3067      int newd;
3068 {
3069   register int fd, ret;
3070
3071   sys_close (newd);
3072
3073 #ifdef F_DUPFD
3074   fd = fcntl (oldd, F_DUPFD, newd);
3075   if (fd != newd)
3076     error ("can't dup2 (%i,%i) : %s", oldd, newd, strerror (errno));
3077 #else
3078   fd = dup (old);
3079   if (fd == -1)
3080     return -1;
3081   if (fd == new)
3082     return new;
3083   ret = dup2 (old,new);
3084   sys_close (fd);
3085   return ret;
3086 #endif
3087 }
3088
3089 #endif /* not HAVE_DUP2 */
3090
3091 /*
3092  *      Gettimeofday.  Simulate as much as possible.  Only accurate
3093  *      to nearest second.  Emacs doesn't use tzp so ignore it for now.
3094  *      Only needed when subprocesses are defined.
3095  */
3096
3097 #ifdef subprocesses
3098 #ifndef VMS
3099 #ifndef HAVE_GETTIMEOFDAY
3100 #ifdef HAVE_TIMEVAL
3101
3102 /* ARGSUSED */
3103 gettimeofday (tp, tzp)
3104      struct timeval *tp;
3105      struct timezone *tzp;
3106 {
3107   extern long time ();
3108
3109   tp->tv_sec = time ((long *)0);
3110   tp->tv_usec = 0;
3111   if (tzp != 0)
3112     tzp->tz_minuteswest = -1;
3113 }
3114
3115 #endif
3116 #endif
3117 #endif
3118 #endif /* subprocess && !HAVE_GETTIMEOFDAY && HAVE_TIMEVAL && !VMS */
3119
3120 /*
3121  *      This function will go away as soon as all the stubs fixed. (fnf)
3122  */
3123
3124 croak (badfunc)
3125      char *badfunc;
3126 {
3127   printf ("%s not yet implemented\r\n", badfunc);
3128   reset_sys_modes ();
3129   exit (1);
3130 }
3131
3132 #endif /* USG */
3133 \f
3134 #ifdef DGUX
3135
3136 char *sys_siglist[NSIG + 1] =
3137 {
3138   "null signal",                         /*  0 SIGNULL   */
3139   "hangup",                              /*  1 SIGHUP    */
3140   "interrupt",                           /*  2 SIGINT    */
3141   "quit",                                /*  3 SIGQUIT   */
3142   "illegal instruction",                 /*  4 SIGILL    */
3143   "trace trap",                          /*  5 SIGTRAP   */
3144   "abort termination",                   /*  6 SIGABRT   */
3145   "SIGEMT",                              /*  7 SIGEMT    */
3146   "floating point exception",            /*  8 SIGFPE    */
3147   "kill",                                /*  9 SIGKILL   */
3148   "bus error",                           /* 10 SIGBUS    */
3149   "segmentation violation",              /* 11 SIGSEGV   */
3150   "bad argument to system call",         /* 12 SIGSYS    */
3151   "write on a pipe with no reader",      /* 13 SIGPIPE   */
3152   "alarm clock",                         /* 14 SIGALRM   */
3153   "software termination signal",         /* 15 SIGTERM   */
3154   "user defined signal 1",               /* 16 SIGUSR1   */
3155   "user defined signal 2",               /* 17 SIGUSR2   */
3156   "child stopped or terminated",         /* 18 SIGCLD    */
3157   "power-fail restart",                  /* 19 SIGPWR    */
3158   "window size changed",                 /* 20 SIGWINCH  */
3159   "undefined",                           /* 21           */
3160   "pollable event occurred",             /* 22 SIGPOLL   */
3161   "sendable stop signal not from tty",   /* 23 SIGSTOP   */
3162   "stop signal from tty",                /* 24 SIGSTP    */
3163   "continue a stopped process",          /* 25 SIGCONT   */
3164   "attempted background tty read",       /* 26 SIGTTIN   */
3165   "attempted background tty write",      /* 27 SIGTTOU   */
3166   "undefined",                           /* 28           */
3167   "undefined",                           /* 29           */
3168   "undefined",                           /* 30           */
3169   "undefined",                           /* 31           */
3170   "undefined",                           /* 32           */
3171   "socket (TCP/IP) urgent data arrival", /* 33 SIGURG    */
3172   "I/O is possible",                     /* 34 SIGIO     */
3173   "exceeded cpu time limit",             /* 35 SIGXCPU   */
3174   "exceeded file size limit",            /* 36 SIGXFSZ   */
3175   "virtual time alarm",                  /* 37 SIGVTALRM */
3176   "profiling time alarm",                /* 38 SIGPROF   */
3177   "undefined",                           /* 39           */
3178   "file record locks revoked",           /* 40 SIGLOST   */
3179   "undefined",                           /* 41           */
3180   "undefined",                           /* 42           */
3181   "undefined",                           /* 43           */
3182   "undefined",                           /* 44           */
3183   "undefined",                           /* 45           */
3184   "undefined",                           /* 46           */
3185   "undefined",                           /* 47           */
3186   "undefined",                           /* 48           */
3187   "undefined",                           /* 49           */
3188   "undefined",                           /* 50           */
3189   "undefined",                           /* 51           */
3190   "undefined",                           /* 52           */
3191   "undefined",                           /* 53           */
3192   "undefined",                           /* 54           */
3193   "undefined",                           /* 55           */
3194   "undefined",                           /* 56           */
3195   "undefined",                           /* 57           */
3196   "undefined",                           /* 58           */
3197   "undefined",                           /* 59           */
3198   "undefined",                           /* 60           */
3199   "undefined",                           /* 61           */
3200   "undefined",                           /* 62           */
3201   "undefined",                           /* 63           */
3202   "notification message in mess. queue", /* 64 SIGDGNOTIFY */
3203   0
3204 };
3205
3206 #endif /* DGUX */
3207 \f
3208 /* Directory routines for systems that don't have them. */
3209
3210 #ifdef SYSV_SYSTEM_DIR
3211
3212 #include <dirent.h>
3213
3214 #if defined(BROKEN_CLOSEDIR) || !defined(HAVE_CLOSEDIR)
3215
3216 int
3217 closedir (dirp)
3218      register DIR *dirp;              /* stream from opendir */
3219 {
3220   int rtnval;
3221
3222   rtnval = sys_close (dirp->dd_fd);
3223
3224   /* Some systems (like Solaris) allocate the buffer and the DIR all
3225      in one block.  Why in the world are we freeing this ourselves
3226      anyway?  */
3227 #if ! (defined (sun) && defined (USG5_4))
3228   xfree ((char *) dirp->dd_buf); /* directory block defined in <dirent.h> */
3229 #endif
3230   xfree ((char *) dirp);
3231
3232   return rtnval;
3233 }
3234 #endif /* BROKEN_CLOSEDIR or not HAVE_CLOSEDIR */
3235 #endif /* SYSV_SYSTEM_DIR */
3236
3237 #ifdef NONSYSTEM_DIR_LIBRARY
3238
3239 DIR *
3240 opendir (filename)
3241      char *filename;    /* name of directory */
3242 {
3243   register DIR *dirp;           /* -> malloc'ed storage */
3244   register int fd;              /* file descriptor for read */
3245   struct stat sbuf;             /* result of fstat */
3246
3247   fd = sys_open (filename, 0);
3248   if (fd < 0)
3249     return 0;
3250
3251   BLOCK_INPUT;
3252   if (fstat (fd, &sbuf) < 0
3253       || (sbuf.st_mode & S_IFMT) != S_IFDIR
3254       || (dirp = (DIR *) malloc (sizeof (DIR))) == 0)
3255     {
3256       sys_close (fd);
3257       UNBLOCK_INPUT;
3258       return 0;         /* bad luck today */
3259     }
3260   UNBLOCK_INPUT;
3261
3262   dirp->dd_fd = fd;
3263   dirp->dd_loc = dirp->dd_size = 0;     /* refill needed */
3264
3265   return dirp;
3266 }
3267
3268 void
3269 closedir (dirp)
3270      register DIR *dirp;                /* stream from opendir */
3271 {
3272   sys_close (dirp->dd_fd);
3273   xfree ((char *) dirp);
3274 }
3275
3276
3277 #ifndef VMS
3278 #define DIRSIZ  14
3279 struct olddir
3280   {
3281     ino_t od_ino;               /* inode */
3282     char od_name[DIRSIZ];       /* filename */
3283   };
3284 #endif /* not VMS */
3285
3286 struct direct dir_static;       /* simulated directory contents */
3287
3288 /* ARGUSED */
3289 struct direct *
3290 readdir (dirp)
3291      register DIR *dirp;        /* stream from opendir */
3292 {
3293 #ifndef VMS
3294   register struct olddir *dp;   /* -> directory data */
3295 #else /* VMS */
3296   register struct dir$_name *dp; /* -> directory data */
3297   register struct dir$_version *dv; /* -> version data */
3298 #endif /* VMS */
3299
3300   for (; ;)
3301     {
3302       if (dirp->dd_loc >= dirp->dd_size)
3303         dirp->dd_loc = dirp->dd_size = 0;
3304
3305       if (dirp->dd_size == 0    /* refill buffer */
3306           && (dirp->dd_size = sys_read (dirp->dd_fd, dirp->dd_buf, DIRBLKSIZ)) <= 0)
3307         return 0;
3308
3309 #ifndef VMS
3310       dp = (struct olddir *) &dirp->dd_buf[dirp->dd_loc];
3311       dirp->dd_loc += sizeof (struct olddir);
3312
3313       if (dp->od_ino != 0)      /* not deleted entry */
3314         {
3315           dir_static.d_ino = dp->od_ino;
3316           strncpy (dir_static.d_name, dp->od_name, DIRSIZ);
3317           dir_static.d_name[DIRSIZ] = '\0';
3318           dir_static.d_namlen = strlen (dir_static.d_name);
3319           dir_static.d_reclen = sizeof (struct direct)
3320             - MAXNAMLEN + 3
3321               + dir_static.d_namlen - dir_static.d_namlen % 4;
3322           return &dir_static;   /* -> simulated structure */
3323         }
3324 #else /* VMS */
3325       dp = (struct dir$_name *) dirp->dd_buf;
3326       if (dirp->dd_loc == 0)
3327         dirp->dd_loc = (dp->dir$b_namecount&1) ? dp->dir$b_namecount + 1
3328           : dp->dir$b_namecount;
3329       dv = (struct dir$_version *)&dp->dir$t_name[dirp->dd_loc];
3330       dir_static.d_ino = dv->dir$w_fid_num;
3331       dir_static.d_namlen = dp->dir$b_namecount;
3332       dir_static.d_reclen = sizeof (struct direct)
3333         - MAXNAMLEN + 3
3334           + dir_static.d_namlen - dir_static.d_namlen % 4;
3335       strncpy (dir_static.d_name, dp->dir$t_name, dp->dir$b_namecount);
3336       dir_static.d_name[dir_static.d_namlen] = '\0';
3337       dirp->dd_loc = dirp->dd_size; /* only one record at a time */
3338       return &dir_static;
3339 #endif /* VMS */
3340     }
3341 }
3342
3343 #ifdef VMS
3344 /* readdirver is just like readdir except it returns all versions of a file
3345    as separate entries.  */
3346
3347 /* ARGUSED */
3348 struct direct *
3349 readdirver (dirp)
3350      register DIR *dirp;        /* stream from opendir */
3351 {
3352   register struct dir$_name *dp; /* -> directory data */
3353   register struct dir$_version *dv; /* -> version data */
3354
3355   if (dirp->dd_loc >= dirp->dd_size - sizeof (struct dir$_name))
3356     dirp->dd_loc = dirp->dd_size = 0;
3357
3358   if (dirp->dd_size == 0        /* refill buffer */
3359       && (dirp->dd_size = sys_read (dirp->dd_fd, dirp->dd_buf, DIRBLKSIZ)) <= 0)
3360     return 0;
3361
3362   dp = (struct dir$_name *) dirp->dd_buf;
3363   if (dirp->dd_loc == 0)
3364     dirp->dd_loc = (dp->dir$b_namecount & 1) ? dp->dir$b_namecount + 1
3365                    : dp->dir$b_namecount;
3366   dv = (struct dir$_version *) &dp->dir$t_name[dirp->dd_loc];
3367   strncpy (dir_static.d_name, dp->dir$t_name, dp->dir$b_namecount);
3368   sprintf (&dir_static.d_name[dp->dir$b_namecount], ";%d", dv->dir$w_version);
3369   dir_static.d_namlen = strlen (dir_static.d_name);
3370   dir_static.d_ino = dv->dir$w_fid_num;
3371   dir_static.d_reclen = sizeof (struct direct) - MAXNAMLEN + 3
3372                         + dir_static.d_namlen - dir_static.d_namlen % 4;
3373   dirp->dd_loc = ((char *) (++dv) - dp->dir$t_name);
3374   return &dir_static;
3375 }
3376
3377 #endif /* VMS */
3378
3379 #endif /* NONSYSTEM_DIR_LIBRARY */
3380
3381 \f
3382 int
3383 set_file_times (filename, atime, mtime)
3384      char *filename;
3385      EMACS_TIME atime, mtime;
3386 {
3387 #ifdef HAVE_UTIMES
3388   struct timeval tv[2];
3389   tv[0] = atime;
3390   tv[1] = mtime;
3391   return utimes (filename, tv);
3392 #else /* not HAVE_UTIMES */
3393   struct utimbuf utb;
3394   utb.actime = EMACS_SECS (atime);
3395   utb.modtime = EMACS_SECS (mtime);
3396   return utime (filename, &utb);
3397 #endif /* not HAVE_UTIMES */
3398 }
3399 \f
3400 /* mkdir and rmdir functions, for systems which don't have them.  */
3401
3402 #ifndef HAVE_MKDIR
3403 /*
3404  * Written by Robert Rother, Mariah Corporation, August 1985.
3405  *
3406  * If you want it, it's yours.  All I ask in return is that if you
3407  * figure out how to do this in a Bourne Shell script you send me
3408  * a copy.
3409  *                                      sdcsvax!rmr or rmr@uscd
3410  *
3411  * Severely hacked over by John Gilmore to make a 4.2BSD compatible
3412  * subroutine.  11Mar86; hoptoad!gnu
3413  *
3414  * Modified by rmtodd@uokmax 6-28-87 -- when making an already existing dir,
3415  * subroutine didn't return EEXIST.  It does now.
3416  */
3417
3418 /*
3419  * Make a directory.
3420  */
3421 #ifdef MKDIR_PROTOTYPE
3422 MKDIR_PROTOTYPE
3423 #else
3424 int
3425 mkdir (dpath, dmode)
3426      char *dpath;
3427      int dmode;
3428 #endif
3429 {
3430   int cpid, status, fd;
3431   struct stat statbuf;
3432
3433   if (stat (dpath, &statbuf) == 0)
3434     {
3435       errno = EEXIST;           /* Stat worked, so it already exists */
3436       return -1;
3437     }
3438
3439   /* If stat fails for a reason other than non-existence, return error */
3440   if (errno != ENOENT)
3441     return -1;
3442
3443   synch_process_alive = 1;
3444   switch (cpid = fork ())
3445     {
3446
3447     case -1:                    /* Error in fork */
3448       return (-1);              /* Errno is set already */
3449
3450     case 0:                     /* Child process */
3451       /*
3452                  * Cheap hack to set mode of new directory.  Since this
3453                  * child process is going away anyway, we zap its umask.
3454                  * FIXME, this won't suffice to set SUID, SGID, etc. on this
3455                  * directory.  Does anybody care?
3456                  */
3457       status = umask (0);       /* Get current umask */
3458       status = umask (status | (0777 & ~dmode));        /* Set for mkdir */
3459       fd = sys_open("/dev/null", 2);
3460       if (fd >= 0)
3461         {
3462           dup2 (fd, 0);
3463           dup2 (fd, 1);
3464           dup2 (fd, 2);
3465         }
3466       execl ("/bin/mkdir", "mkdir", dpath, (char *) 0);
3467       _exit (-1);               /* Can't exec /bin/mkdir */
3468
3469     default:                    /* Parent process */
3470       wait_for_termination (cpid);
3471     }
3472
3473   if (synch_process_death != 0 || synch_process_retcode != 0)
3474     {
3475       errno = EIO;              /* We don't know why, but */
3476       return -1;                /* /bin/mkdir failed */
3477     }
3478
3479   return 0;
3480 }
3481 #endif /* not HAVE_MKDIR */
3482
3483 #ifndef HAVE_RMDIR
3484 int
3485 rmdir (dpath)
3486      char *dpath;
3487 {
3488   int cpid, status, fd;
3489   struct stat statbuf;
3490
3491   if (stat (dpath, &statbuf) != 0)
3492     {
3493       /* Stat just set errno.  We don't have to */
3494       return -1;
3495     }
3496
3497   synch_process_alive = 1;
3498   switch (cpid = fork ())
3499     {
3500
3501     case -1:                    /* Error in fork */
3502       return (-1);              /* Errno is set already */
3503
3504     case 0:                     /* Child process */
3505       fd = sys_open("/dev/null", 2);
3506       if (fd >= 0)
3507         {
3508           dup2 (fd, 0);
3509           dup2 (fd, 1);
3510           dup2 (fd, 2);
3511         }
3512       wait_for_termination (cpid);
3513   if (synch_process_death != 0 || synch_process_retcode != 0)
3514       return -1;                /* /bin/rmdir failed */
3515     default:                    /* Parent process */
3516       while (cpid != wait (&status));   /* Wait for kid to finish */
3517     }
3518
3519   if (WIFSIGNALED (status) || WEXITSTATUS (status) != 0)
3520     {
3521       errno = EIO;              /* We don't know why, but */
3522       return -1;                /* /bin/mkdir failed */
3523     }
3524
3525   return 0;
3526 }
3527 #endif /* !HAVE_RMDIR */
3528
3529
3530 \f
3531 /* Functions for VMS */
3532 #ifdef VMS
3533 #include "vms-pwd.h"
3534 #include <acldef.h>
3535 #include <chpdef.h>
3536 #include <jpidef.h>
3537
3538 /* Return as a string the VMS error string pertaining to STATUS.
3539    Reuses the same static buffer each time it is called.  */
3540
3541 char *
3542 vmserrstr (status)
3543      int status;                /* VMS status code */
3544 {
3545   int bufadr[2];
3546   short len;
3547   static char buf[257];
3548
3549   bufadr[0] = sizeof buf - 1;
3550   bufadr[1] = (int) buf;
3551   if (! (SYS$GETMSG (status, &len, bufadr, 0x1, 0) & 1))
3552     return "untranslatable VMS error status";
3553   buf[len] = '\0';
3554   return buf;
3555 }
3556
3557 #ifdef access
3558 #undef access
3559
3560 /* The following is necessary because 'access' emulation by VMS C (2.0) does
3561  * not work correctly.  (It also doesn't work well in version 2.3.)
3562  */
3563
3564 #ifdef VMS4_4
3565
3566 #define DESCRIPTOR(name,string) struct dsc$descriptor_s name = \
3567         { strlen (string), DSC$K_DTYPE_T, DSC$K_CLASS_S, string }
3568
3569 typedef union {
3570     struct {
3571         unsigned short s_buflen;
3572         unsigned short s_code;
3573         char *s_bufadr;
3574         unsigned short *s_retlenadr;
3575     } s;
3576     int end;
3577 } item;
3578 #define buflen s.s_buflen
3579 #define code s.s_code
3580 #define bufadr s.s_bufadr
3581 #define retlenadr s.s_retlenadr
3582
3583 #define R_OK 4  /* test for read permission */
3584 #define W_OK 2  /* test for write permission */
3585 #define X_OK 1  /* test for execute (search) permission */
3586 #define F_OK 0  /* test for presence of file */
3587
3588 int
3589 sys_access (path, mode)
3590      char *path;
3591      int mode;
3592 {
3593   static char *user = NULL;
3594   char dir_fn[512];
3595
3596   /* translate possible directory spec into .DIR file name, so brain-dead
3597    * access can treat the directory like a file.  */
3598   if (directory_file_name (path, dir_fn))
3599     path = dir_fn;
3600
3601   if (mode == F_OK)
3602     return access (path, mode);
3603   if (user == NULL && (user = (char *) getenv ("USER")) == NULL)
3604     return -1;
3605   {
3606     int stat;
3607     int flags;
3608     int acces;
3609     unsigned short int dummy;
3610     item itemlst[3];
3611     static int constant = ACL$C_FILE;
3612     DESCRIPTOR (path_desc, path);
3613     DESCRIPTOR (user_desc, user);
3614
3615     flags = 0;
3616     acces = 0;
3617     if ((mode & X_OK) && ((stat = access (path, mode)) < 0 || mode == X_OK))
3618       return stat;
3619     if (mode & R_OK)
3620       acces |= CHP$M_READ;
3621     if (mode & W_OK)
3622       acces |= CHP$M_WRITE;
3623     itemlst[0].buflen = sizeof (int);
3624     itemlst[0].code = CHP$_FLAGS;
3625     itemlst[0].bufadr = (char *) &flags;
3626     itemlst[0].retlenadr = &dummy;
3627     itemlst[1].buflen = sizeof (int);
3628     itemlst[1].code = CHP$_ACCESS;
3629     itemlst[1].bufadr = (char *) &acces;
3630     itemlst[1].retlenadr = &dummy;
3631     itemlst[2].end = CHP$_END;
3632     stat = SYS$CHECK_ACCESS (&constant, &path_desc, &user_desc, itemlst);
3633     return stat == SS$_NORMAL ? 0 : -1;
3634   }
3635 }
3636
3637 #else /* not VMS4_4 */
3638
3639 #include <prvdef.h>
3640 #define ACE$M_WRITE     2
3641 #define ACE$C_KEYID     1
3642
3643 static unsigned short memid, grpid;
3644 static unsigned int uic;
3645
3646 /* Called from init_sys_modes, so it happens not very often
3647    but at least each time Emacs is loaded.  */
3648 sys_access_reinit ()
3649 {
3650   uic = 0;
3651 }
3652
3653 int
3654 sys_access (filename, type)
3655      char * filename;
3656      int type;
3657 {
3658   struct FAB fab;
3659   struct XABPRO xab;
3660   int status, size, i, typecode, acl_controlled;
3661   unsigned int *aclptr, *aclend, aclbuf[60];
3662   union prvdef prvmask;
3663
3664   /* Get UIC and GRP values for protection checking.  */
3665   if (uic == 0)
3666     {
3667       status = LIB$GETJPI (&JPI$_UIC, 0, 0, &uic, 0, 0);
3668       if (! (status & 1))
3669         return -1;
3670       memid = uic & 0xFFFF;
3671       grpid = uic >> 16;
3672     }
3673
3674   if (type != 2)                /* not checking write access */
3675     return access (filename, type);
3676
3677   /* Check write protection. */
3678
3679 #define CHECKPRIV(bit)    (prvmask.bit)
3680 #define WRITEABLE(field)  (! ((xab.xab$w_pro >> field) & XAB$M_NOWRITE))
3681
3682   /* Find privilege bits */
3683   status = SYS$SETPRV (0, 0, 0, prvmask);
3684   if (! (status & 1))
3685     error ("Unable to find privileges: %s", vmserrstr (status));
3686   if (CHECKPRIV (PRV$V_BYPASS))
3687     return 0;                   /* BYPASS enabled */
3688   fab = cc$rms_fab;
3689   fab.fab$b_fac = FAB$M_GET;
3690   fab.fab$l_fna = filename;
3691   fab.fab$b_fns = strlen (filename);
3692   fab.fab$l_xab = &xab;
3693   xab = cc$rms_xabpro;
3694   xab.xab$l_aclbuf = aclbuf;
3695   xab.xab$w_aclsiz = sizeof (aclbuf);
3696   status = SYS$OPEN (&fab, 0, 0);
3697   if (! (status & 1))
3698     return -1;
3699   SYS$CLOSE (&fab, 0, 0);
3700   /* Check system access */
3701   if (CHECKPRIV (PRV$V_SYSPRV) && WRITEABLE (XAB$V_SYS))
3702     return 0;
3703   /* Check ACL entries, if any */
3704   acl_controlled = 0;
3705   if (xab.xab$w_acllen > 0)
3706     {
3707       aclptr = aclbuf;
3708       aclend = &aclbuf[xab.xab$w_acllen / 4];
3709       while (*aclptr && aclptr < aclend)
3710         {
3711           size = (*aclptr & 0xff) / 4;
3712           typecode = (*aclptr >> 8) & 0xff;
3713           if (typecode == ACE$C_KEYID)
3714             for (i = size - 1; i > 1; i--)
3715               if (aclptr[i] == uic)
3716                 {
3717                   acl_controlled = 1;
3718                   if (aclptr[1] & ACE$M_WRITE)
3719                     return 0;   /* Write access through ACL */
3720                 }
3721           aclptr = &aclptr[size];
3722         }
3723       if (acl_controlled)       /* ACL specified, prohibits write access */
3724         return -1;
3725     }
3726   /* No ACL entries specified, check normal protection */
3727   if (WRITEABLE (XAB$V_WLD))    /* World writeable */
3728     return 0;
3729   if (WRITEABLE (XAB$V_GRP) &&
3730       (unsigned short) (xab.xab$l_uic >> 16) == grpid)
3731     return 0;                   /* Group writeable */
3732   if (WRITEABLE (XAB$V_OWN) &&
3733       (xab.xab$l_uic & 0xFFFF) == memid)
3734     return 0;                   /* Owner writeable */
3735
3736   return -1;    /* Not writeable */
3737 }
3738 #endif /* not VMS4_4 */
3739 #endif /* access */
3740
3741 static char vtbuf[NAM$C_MAXRSS+1];
3742
3743 /* translate a vms file spec to a unix path */
3744 char *
3745 sys_translate_vms (vfile)
3746      char * vfile;
3747 {
3748   char * p;
3749   char * targ;
3750
3751   if (!vfile)
3752     return 0;
3753
3754   targ = vtbuf;
3755
3756   /* leading device or logical name is a root directory */
3757   if (p = strchr (vfile, ':'))
3758     {
3759       *targ++ = '/';
3760       while (vfile < p)
3761         *targ++ = *vfile++;
3762       vfile++;
3763       *targ++ = '/';
3764     }
3765   p = vfile;
3766   if (*p == '[' || *p == '<')
3767     {
3768       while (*++vfile != *p + 2)
3769         switch (*vfile)
3770           {
3771           case '.':
3772             if (vfile[-1] == *p)
3773               *targ++ = '.';
3774             *targ++ = '/';
3775             break;
3776
3777           case '-':
3778             *targ++ = '.';
3779             *targ++ = '.';
3780             break;
3781
3782           default:
3783             *targ++ = *vfile;
3784             break;
3785           }
3786       vfile++;
3787       *targ++ = '/';
3788     }
3789   while (*vfile)
3790     *targ++ = *vfile++;
3791
3792   return vtbuf;
3793 }
3794
3795 static char utbuf[NAM$C_MAXRSS+1];
3796
3797 /* translate a unix path to a VMS file spec */
3798 char *
3799 sys_translate_unix (ufile)
3800      char * ufile;
3801 {
3802   int slash_seen = 0;
3803   char *p;
3804   char * targ;
3805
3806   if (!ufile)
3807     return 0;
3808
3809   targ = utbuf;
3810
3811   if (*ufile == '/')
3812     {
3813       ufile++;
3814     }
3815
3816   while (*ufile)
3817     {
3818       switch (*ufile)
3819         {
3820         case '/':
3821           if (slash_seen)
3822             if (index (&ufile[1], '/'))
3823               *targ++ = '.';
3824             else
3825               *targ++ = ']';
3826           else
3827             {
3828               *targ++ = ':';
3829               if (index (&ufile[1], '/'))
3830                 *targ++ = '[';
3831               slash_seen = 1;
3832             }
3833           break;
3834
3835         case '.':
3836           if (strncmp (ufile, "./", 2) == 0)
3837             {
3838               if (!slash_seen)
3839                 {
3840                   *targ++ = '[';
3841                   slash_seen = 1;
3842                 }
3843               ufile++;          /* skip the dot */
3844               if (index (&ufile[1], '/'))
3845                 *targ++ = '.';
3846               else
3847                 *targ++ = ']';
3848             }
3849           else if (strncmp (ufile, "../", 3) == 0)
3850             {
3851               if (!slash_seen)
3852                 {
3853                   *targ++ = '[';
3854                   slash_seen = 1;
3855                 }
3856               *targ++ = '-';
3857               ufile += 2;       /* skip the dots */
3858               if (index (&ufile[1], '/'))
3859                 *targ++ = '.';
3860               else
3861                 *targ++ = ']';
3862             }
3863           else
3864             *targ++ = *ufile;
3865           break;
3866
3867         default:
3868           *targ++ = *ufile;
3869           break;
3870         }
3871       ufile++;
3872     }
3873   *targ = '\0';
3874
3875   return utbuf;
3876 }
3877
3878 char *
3879 getwd (pathname)
3880      char *pathname;
3881 {
3882   char *ptr, *val;
3883   extern char *getcwd ();
3884
3885 #define MAXPATHLEN 1024
3886
3887   ptr = xmalloc (MAXPATHLEN);
3888   val = getcwd (ptr, MAXPATHLEN);
3889   if (val == 0)
3890     {
3891       xfree (ptr);
3892       return val;
3893     }
3894   strcpy (pathname, ptr);
3895   xfree (ptr);
3896
3897  return pathname;
3898 }
3899
3900 getppid ()
3901 {
3902   long item_code = JPI$_OWNER;
3903   unsigned long parent_id;
3904   int status;
3905
3906   if (((status = LIB$GETJPI (&item_code, 0, 0, &parent_id)) & 1) == 0)
3907     {
3908       errno = EVMSERR;
3909       vaxc$errno = status;
3910       return -1;
3911     }
3912   return parent_id;
3913 }
3914
3915 #undef getuid
3916 unsigned
3917 sys_getuid ()
3918 {
3919   return (getgid () << 16) | getuid ();
3920 }
3921
3922 int
3923 sys_read (fildes, buf, nbyte)
3924      int fildes;
3925      char *buf;
3926      unsigned int nbyte;
3927 {
3928   return read (fildes, buf, (nbyte < MAXIOSIZE ? nbyte : MAXIOSIZE));
3929 }
3930
3931 #if 0
3932 int
3933 sys_write (fildes, buf, nbyte)
3934      int fildes;
3935      char *buf;
3936      unsigned int nbyte;
3937 {
3938   register int nwrote, rtnval = 0;
3939
3940   while (nbyte > MAXIOSIZE && (nwrote = write (fildes, buf, MAXIOSIZE)) > 0) {
3941     nbyte -= nwrote;
3942     buf += nwrote;
3943     rtnval += nwrote;
3944   }
3945   if (nwrote < 0)
3946     return rtnval ? rtnval : -1;
3947   if ((nwrote = write (fildes, buf, nbyte)) < 0)
3948     return rtnval ? rtnval : -1;
3949   return (rtnval + nwrote);
3950 }
3951 #endif /* 0 */
3952
3953 /*
3954  *      VAX/VMS VAX C RTL really loses. It insists that records
3955  *      end with a newline (carriage return) character, and if they
3956  *      don't it adds one (nice of it isn't it!)
3957  *
3958  *      Thus we do this stupidity below.
3959  */
3960
3961 int
3962 sys_write (fildes, buf, nbytes)
3963      int fildes;
3964      char *buf;
3965      unsigned int nbytes;
3966 {
3967   register char *p;
3968   register char *e;
3969   int sum = 0;
3970   struct stat st;
3971
3972   fstat (fildes, &st);
3973   p = buf;
3974   while (nbytes > 0)
3975     {
3976       int len, retval;
3977
3978       /* Handle fixed-length files with carriage control.  */
3979       if (st.st_fab_rfm == FAB$C_FIX
3980           && ((st.st_fab_rat & (FAB$M_FTN | FAB$M_CR)) != 0))
3981         {
3982           len = st.st_fab_mrs;
3983           retval = write (fildes, p, min (len, nbytes));
3984           if (retval != len)
3985             return -1;
3986           retval++;     /* This skips the implied carriage control */
3987         }
3988       else
3989         {
3990           e =  p + min (MAXIOSIZE, nbytes) - 1;
3991           while (*e != '\n' && e > p) e--;
3992           if (p == e)           /* Ok.. so here we add a newline... sigh. */
3993             e = p + min (MAXIOSIZE, nbytes) - 1;
3994           len = e + 1 - p;
3995           retval = write (fildes, p, len);
3996           if (retval != len)
3997             return -1;
3998         }
3999       p += retval;
4000       sum += retval;
4001       nbytes -= retval;
4002     }
4003   return sum;
4004 }
4005
4006 /* Create file NEW copying its attributes from file OLD.  If
4007    OLD is 0 or does not exist, create based on the value of
4008    vms_stmlf_recfm. */
4009
4010 /* Protection value the file should ultimately have.
4011    Set by create_copy_attrs, and use by rename_sansversions.  */
4012 static unsigned short int fab_final_pro;
4013
4014 int
4015 creat_copy_attrs (old, new)
4016      char *old, *new;
4017 {
4018   struct FAB fab = cc$rms_fab;
4019   struct XABPRO xabpro;
4020   char aclbuf[256];     /* Choice of size is arbitrary.  See below. */
4021   extern int vms_stmlf_recfm;
4022
4023   if (old)
4024     {
4025       fab.fab$b_fac = FAB$M_GET;
4026       fab.fab$l_fna = old;
4027       fab.fab$b_fns = strlen (old);
4028       fab.fab$l_xab = (char *) &xabpro;
4029       xabpro = cc$rms_xabpro;
4030       xabpro.xab$l_aclbuf = aclbuf;
4031       xabpro.xab$w_aclsiz = sizeof aclbuf;
4032       /* Call $OPEN to fill in the fab & xabpro fields. */
4033       if (SYS$OPEN (&fab, 0, 0) & 1)
4034         {
4035           SYS$CLOSE (&fab, 0, 0);
4036           fab.fab$l_alq = 0;    /* zero the allocation quantity */
4037           if (xabpro.xab$w_acllen > 0)
4038             {
4039               if (xabpro.xab$w_acllen > sizeof aclbuf)
4040                 /* If the acl buffer was too short, redo open with longer one.
4041                    Wouldn't need to do this if there were some system imposed
4042                    limit on the size of an ACL, but I can't find any such. */
4043                 {
4044                   xabpro.xab$l_aclbuf = (char *) alloca (xabpro.xab$w_acllen);
4045                   xabpro.xab$w_aclsiz = xabpro.xab$w_acllen;
4046                   if (SYS$OPEN (&fab, 0, 0) & 1)
4047                     SYS$CLOSE (&fab, 0, 0);
4048                   else
4049                     old = 0;
4050                 }
4051             }
4052           else
4053             xabpro.xab$l_aclbuf = 0;
4054         }
4055       else
4056         old = 0;
4057     }
4058   fab.fab$l_fna = new;
4059   fab.fab$b_fns = strlen (new);
4060   if (!old)
4061     {
4062       fab.fab$l_xab = 0;
4063       fab.fab$b_rfm = vms_stmlf_recfm ? FAB$C_STMLF : FAB$C_VAR;
4064       fab.fab$b_rat = FAB$M_CR;
4065     }
4066
4067   /* Set the file protections such that we will be able to manipulate
4068      this file.  Once we are done writing and renaming it, we will set
4069      the protections back.  */
4070   if (old)
4071     fab_final_pro = xabpro.xab$w_pro;
4072   else
4073     SYS$SETDFPROT (0, &fab_final_pro);
4074   xabpro.xab$w_pro &= 0xff0f; /* set O:rewd for now. This is set back later. */
4075
4076   /* Create the new file with either default attrs or attrs copied
4077      from old file. */
4078   if (!(SYS$CREATE (&fab, 0, 0) & 1))
4079     return -1;
4080   SYS$CLOSE (&fab, 0, 0);
4081   /* As this is a "replacement" for creat, return a file descriptor
4082      opened for writing. */
4083   return open (new, O_WRONLY);
4084 }
4085
4086 #ifdef creat
4087 #undef creat
4088 #include <varargs.h>
4089 #ifdef __GNUC__
4090 #ifndef va_count
4091 #define va_count(X) ((X) = *(((int *) &(va_alist)) - 1))
4092 #endif
4093 #endif
4094
4095 sys_creat (va_alist)
4096      va_dcl
4097 {
4098   va_list list_incrementer;
4099   char *name;
4100   int mode;
4101   int rfd;                      /* related file descriptor */
4102   int fd;                       /* Our new file descriptor */
4103   int count;
4104   struct stat st_buf;
4105   char rfm[12];
4106   char rat[15];
4107   char mrs[13];
4108   char fsz[13];
4109   extern int vms_stmlf_recfm;
4110
4111   va_count (count);
4112   va_start (list_incrementer);
4113   name = va_arg (list_incrementer, char *);
4114   mode = va_arg (list_incrementer, int);
4115   if (count > 2)
4116     rfd = va_arg (list_incrementer, int);
4117   va_end (list_incrementer);
4118   if (count > 2)
4119     {
4120       /* Use information from the related file descriptor to set record
4121          format of the newly created file. */
4122       fstat (rfd, &st_buf);
4123       switch (st_buf.st_fab_rfm)
4124         {
4125         case FAB$C_FIX:
4126           strcpy (rfm, "rfm = fix");
4127           sprintf (mrs, "mrs = %d", st_buf.st_fab_mrs);
4128           strcpy (rat, "rat = ");
4129           if (st_buf.st_fab_rat & FAB$M_CR)
4130             strcat (rat, "cr");
4131           else if (st_buf.st_fab_rat & FAB$M_FTN)
4132             strcat (rat, "ftn");
4133           else if (st_buf.st_fab_rat & FAB$M_PRN)
4134             strcat (rat, "prn");
4135           if (st_buf.st_fab_rat & FAB$M_BLK)
4136             if (st_buf.st_fab_rat & (FAB$M_CR|FAB$M_FTN|FAB$M_PRN))
4137               strcat (rat, ", blk");
4138             else
4139               strcat (rat, "blk");
4140           return creat (name, 0, rfm, rat, mrs);
4141
4142         case FAB$C_VFC:
4143           strcpy (rfm, "rfm = vfc");
4144           sprintf (fsz, "fsz = %d", st_buf.st_fab_fsz);
4145           strcpy (rat, "rat = ");
4146           if (st_buf.st_fab_rat & FAB$M_CR)
4147             strcat (rat, "cr");
4148           else if (st_buf.st_fab_rat & FAB$M_FTN)
4149             strcat (rat, "ftn");
4150           else if (st_buf.st_fab_rat & FAB$M_PRN)
4151             strcat (rat, "prn");
4152           if (st_buf.st_fab_rat & FAB$M_BLK)
4153             if (st_buf.st_fab_rat & (FAB$M_CR|FAB$M_FTN|FAB$M_PRN))
4154               strcat (rat, ", blk");
4155             else
4156               strcat (rat, "blk");
4157           return creat (name, 0, rfm, rat, fsz);
4158
4159         case FAB$C_STM:
4160           strcpy (rfm, "rfm = stm");
4161           break;
4162
4163         case FAB$C_STMCR:
4164           strcpy (rfm, "rfm = stmcr");
4165           break;
4166
4167         case FAB$C_STMLF:
4168           strcpy (rfm, "rfm = stmlf");
4169           break;
4170
4171         case FAB$C_UDF:
4172           strcpy (rfm, "rfm = udf");
4173           break;
4174
4175         case FAB$C_VAR:
4176           strcpy (rfm, "rfm = var");
4177           break;
4178         }
4179       strcpy (rat, "rat = ");
4180       if (st_buf.st_fab_rat & FAB$M_CR)
4181         strcat (rat, "cr");
4182       else if (st_buf.st_fab_rat & FAB$M_FTN)
4183         strcat (rat, "ftn");
4184       else if (st_buf.st_fab_rat & FAB$M_PRN)
4185         strcat (rat, "prn");
4186       if (st_buf.st_fab_rat & FAB$M_BLK)
4187         if (st_buf.st_fab_rat & (FAB$M_CR|FAB$M_FTN|FAB$M_PRN))
4188           strcat (rat, ", blk");
4189         else
4190           strcat (rat, "blk");
4191     }
4192   else
4193     {
4194       strcpy (rfm, vms_stmlf_recfm ? "rfm = stmlf" : "rfm=var");
4195       strcpy (rat, "rat=cr");
4196     }
4197   /* Until the VAX C RTL fixes the many bugs with modes, always use
4198      mode 0 to get the user's default protection. */
4199   fd = creat (name, 0, rfm, rat);
4200   if (fd < 0 && errno == EEXIST)
4201     {
4202       if (unlink (name) < 0)
4203         report_file_error ("delete", build_string (name));
4204       fd = creat (name, 0, rfm, rat);
4205     }
4206   return fd;
4207 }
4208 #endif /* creat */
4209
4210 /* fwrite to stdout is S L O W.  Speed it up by using fputc...*/
4211 sys_fwrite (ptr, size, num, fp)
4212      register char * ptr;
4213      FILE * fp;
4214 {
4215   register int tot = num * size;
4216
4217   while (tot--)
4218     fputc (*ptr++, fp);
4219 }
4220
4221 /*
4222  * The VMS C library routine creat actually creates a new version of an
4223  * existing file rather than truncating the old version.  There are times
4224  * when this is not the desired behavior, for instance, when writing an
4225  * auto save file (you only want one version), or when you don't have
4226  * write permission in the directory containing the file (but the file
4227  * itself is writable).  Hence this routine, which is equivalent to
4228  * "close (creat (fn, 0));" on Unix if fn already exists.
4229  */
4230 int
4231 vms_truncate (fn)
4232      char *fn;
4233 {
4234   struct FAB xfab = cc$rms_fab;
4235   struct RAB xrab = cc$rms_rab;
4236   int status;
4237
4238   xfab.fab$l_fop = FAB$M_TEF;   /* free allocated but unused blocks on close */
4239   xfab.fab$b_fac = FAB$M_TRN | FAB$M_GET; /* allow truncate and get access */
4240   xfab.fab$b_shr = FAB$M_NIL;   /* allow no sharing - file must be locked */
4241   xfab.fab$l_fna = fn;
4242   xfab.fab$b_fns = strlen (fn);
4243   xfab.fab$l_dna = ";0";        /* default to latest version of the file */
4244   xfab.fab$b_dns = 2;
4245   xrab.rab$l_fab = &xfab;
4246
4247   /* This gibberish opens the file, positions to the first record, and
4248      deletes all records from there until the end of file. */
4249   if ((SYS$OPEN (&xfab) & 01) == 01)
4250     {
4251       if ((SYS$CONNECT (&xrab) & 01) == 01 &&
4252           (SYS$FIND (&xrab) & 01) == 01 &&
4253           (SYS$TRUNCATE (&xrab) & 01) == 01)
4254         status = 0;
4255       else
4256         status = -1;
4257     }
4258   else
4259     status = -1;
4260   SYS$CLOSE (&xfab);
4261   return status;
4262 }
4263
4264 /* Define this symbol to actually read SYSUAF.DAT.  This requires either
4265    SYSPRV or a readable SYSUAF.DAT. */
4266
4267 #ifdef READ_SYSUAF
4268 /*
4269  * getuaf.c
4270  *
4271  * Routine to read the VMS User Authorization File and return
4272  * a specific user's record.
4273  */
4274
4275 static struct UAF retuaf;
4276
4277 struct UAF *
4278 get_uaf_name (uname)
4279      char * uname;
4280 {
4281   register status;
4282   struct FAB uaf_fab;
4283   struct RAB uaf_rab;
4284
4285   uaf_fab = cc$rms_fab;
4286   uaf_rab = cc$rms_rab;
4287   /* initialize fab fields */
4288   uaf_fab.fab$l_fna = "SYS$SYSTEM:SYSUAF.DAT";
4289   uaf_fab.fab$b_fns = 21;
4290   uaf_fab.fab$b_fac = FAB$M_GET;
4291   uaf_fab.fab$b_org = FAB$C_IDX;
4292   uaf_fab.fab$b_shr = FAB$M_GET|FAB$M_PUT|FAB$M_UPD|FAB$M_DEL;
4293   /* initialize rab fields */
4294   uaf_rab.rab$l_fab = &uaf_fab;
4295   /* open the User Authorization File */
4296   status = SYS$OPEN (&uaf_fab);
4297   if (!(status&1))
4298     {
4299       errno = EVMSERR;
4300       vaxc$errno = status;
4301       return 0;
4302     }
4303   status = SYS$CONNECT (&uaf_rab);
4304   if (!(status&1))
4305     {
4306       errno = EVMSERR;
4307       vaxc$errno = status;
4308       return 0;
4309     }
4310   /* read the requested record - index is in uname */
4311   uaf_rab.rab$l_kbf = uname;
4312   uaf_rab.rab$b_ksz = strlen (uname);
4313   uaf_rab.rab$b_rac = RAB$C_KEY;
4314   uaf_rab.rab$l_ubf = (char *)&retuaf;
4315   uaf_rab.rab$w_usz = sizeof retuaf;
4316   status = SYS$GET (&uaf_rab);
4317   if (!(status&1))
4318     {
4319       errno = EVMSERR;
4320       vaxc$errno = status;
4321       return 0;
4322     }
4323   /* close the User Authorization File */
4324   status = SYS$DISCONNECT (&uaf_rab);
4325   if (!(status&1))
4326     {
4327       errno = EVMSERR;
4328       vaxc$errno = status;
4329       return 0;
4330     }
4331   status = SYS$CLOSE (&uaf_fab);
4332   if (!(status&1))
4333     {
4334       errno = EVMSERR;
4335       vaxc$errno = status;
4336       return 0;
4337     }
4338   return &retuaf;
4339 }
4340
4341 struct UAF *
4342 get_uaf_uic (uic)
4343      unsigned long uic;
4344 {
4345   register status;
4346   struct FAB uaf_fab;
4347   struct RAB uaf_rab;
4348
4349   uaf_fab = cc$rms_fab;
4350   uaf_rab = cc$rms_rab;
4351   /* initialize fab fields */
4352   uaf_fab.fab$l_fna = "SYS$SYSTEM:SYSUAF.DAT";
4353   uaf_fab.fab$b_fns = 21;
4354   uaf_fab.fab$b_fac = FAB$M_GET;
4355   uaf_fab.fab$b_org = FAB$C_IDX;
4356   uaf_fab.fab$b_shr = FAB$M_GET|FAB$M_PUT|FAB$M_UPD|FAB$M_DEL;
4357   /* initialize rab fields */
4358   uaf_rab.rab$l_fab = &uaf_fab;
4359   /* open the User Authorization File */
4360   status = SYS$OPEN (&uaf_fab);
4361   if (!(status&1))
4362     {
4363       errno = EVMSERR;
4364       vaxc$errno = status;
4365       return 0;
4366     }
4367   status = SYS$CONNECT (&uaf_rab);
4368   if (!(status&1))
4369     {
4370       errno = EVMSERR;
4371       vaxc$errno = status;
4372       return 0;
4373     }
4374   /* read the requested record - index is in uic */
4375   uaf_rab.rab$b_krf = 1;        /* 1st alternate key */
4376   uaf_rab.rab$l_kbf = (char *) &uic;
4377   uaf_rab.rab$b_ksz = sizeof uic;
4378   uaf_rab.rab$b_rac = RAB$C_KEY;
4379   uaf_rab.rab$l_ubf = (char *)&retuaf;
4380   uaf_rab.rab$w_usz = sizeof retuaf;
4381   status = SYS$GET (&uaf_rab);
4382   if (!(status&1))
4383     {
4384       errno = EVMSERR;
4385       vaxc$errno = status;
4386       return 0;
4387     }
4388   /* close the User Authorization File */
4389   status = SYS$DISCONNECT (&uaf_rab);
4390   if (!(status&1))
4391     {
4392       errno = EVMSERR;
4393       vaxc$errno = status;
4394       return 0;
4395     }
4396   status = SYS$CLOSE (&uaf_fab);
4397   if (!(status&1))
4398     {
4399       errno = EVMSERR;
4400       vaxc$errno = status;
4401       return 0;
4402     }
4403   return &retuaf;
4404 }
4405
4406 static struct passwd retpw;
4407
4408 struct passwd *
4409 cnv_uaf_pw (up)
4410      struct UAF * up;
4411 {
4412   char * ptr;
4413
4414   /* copy these out first because if the username is 32 chars, the next
4415      section will overwrite the first byte of the UIC */
4416   retpw.pw_uid = up->uaf$w_mem;
4417   retpw.pw_gid = up->uaf$w_grp;
4418
4419   /* I suppose this is not the best sytle, to possibly overwrite one
4420      byte beyond the end of the field, but what the heck... */
4421   ptr = &up->uaf$t_username[UAF$S_USERNAME];
4422   while (ptr[-1] == ' ')
4423     ptr--;
4424   *ptr = '\0';
4425   strcpy (retpw.pw_name, up->uaf$t_username);
4426
4427   /* the rest of these are counted ascii strings */
4428   strncpy (retpw.pw_gecos, &up->uaf$t_owner[1], up->uaf$t_owner[0]);
4429   retpw.pw_gecos[up->uaf$t_owner[0]] = '\0';
4430   strncpy (retpw.pw_dir, &up->uaf$t_defdev[1], up->uaf$t_defdev[0]);
4431   retpw.pw_dir[up->uaf$t_defdev[0]] = '\0';
4432   strncat (retpw.pw_dir, &up->uaf$t_defdir[1], up->uaf$t_defdir[0]);
4433   retpw.pw_dir[up->uaf$t_defdev[0] + up->uaf$t_defdir[0]] = '\0';
4434   strncpy (retpw.pw_shell, &up->uaf$t_defcli[1], up->uaf$t_defcli[0]);
4435   retpw.pw_shell[up->uaf$t_defcli[0]] = '\0';
4436
4437   return &retpw;
4438 }
4439 #else /* not READ_SYSUAF */
4440 static struct passwd retpw;
4441 #endif /* not READ_SYSUAF */
4442
4443 struct passwd *
4444 getpwnam (name)
4445      char * name;
4446 {
4447 #ifdef READ_SYSUAF
4448   struct UAF *up;
4449 #else
4450   char * user;
4451   char * dir;
4452   unsigned char * full;
4453 #endif /* READ_SYSUAF */
4454   char *ptr = name;
4455
4456   while (*ptr)
4457     {
4458       if ('a' <= *ptr && *ptr <= 'z')
4459         *ptr -= 040;
4460       ptr++;
4461     }
4462 #ifdef READ_SYSUAF
4463   if (!(up = get_uaf_name (name)))
4464     return 0;
4465   return cnv_uaf_pw (up);
4466 #else
4467   if (strcmp (name, getenv ("USER")) == 0)
4468     {
4469       retpw.pw_uid = getuid ();
4470       retpw.pw_gid = getgid ();
4471       strcpy (retpw.pw_name, name);
4472       if (full = egetenv ("FULLNAME"))
4473         strcpy (retpw.pw_gecos, full);
4474       else
4475         *retpw.pw_gecos = '\0';
4476       strcpy (retpw.pw_dir, egetenv ("HOME"));
4477       *retpw.pw_shell = '\0';
4478       return &retpw;
4479     }
4480   else
4481     return 0;
4482 #endif /* not READ_SYSUAF */
4483 }
4484
4485 struct passwd *
4486 getpwuid (uid)
4487      unsigned long uid;
4488 {
4489 #ifdef READ_SYSUAF
4490   struct UAF * up;
4491
4492   if (!(up = get_uaf_uic (uid)))
4493     return 0;
4494   return cnv_uaf_pw (up);
4495 #else
4496   if (uid == sys_getuid ())
4497     return getpwnam (egetenv ("USER"));
4498   else
4499     return 0;
4500 #endif /* not READ_SYSUAF */
4501 }
4502
4503 /* return total address space available to the current process.  This is
4504    the sum of the current p0 size, p1 size and free page table entries
4505    available. */
4506 vlimit ()
4507 {
4508   int item_code;
4509   unsigned long free_pages;
4510   unsigned long frep0va;
4511   unsigned long frep1va;
4512   register status;
4513
4514   item_code = JPI$_FREPTECNT;
4515   if (((status = LIB$GETJPI (&item_code, 0, 0, &free_pages)) & 1) == 0)
4516     {
4517       errno = EVMSERR;
4518       vaxc$errno = status;
4519       return -1;
4520     }
4521   free_pages *= 512;
4522
4523   item_code = JPI$_FREP0VA;
4524   if (((status = LIB$GETJPI (&item_code, 0, 0, &frep0va)) & 1) == 0)
4525     {
4526       errno = EVMSERR;
4527       vaxc$errno = status;
4528       return -1;
4529     }
4530   item_code = JPI$_FREP1VA;
4531   if (((status = LIB$GETJPI (&item_code, 0, 0, &frep1va)) & 1) == 0)
4532     {
4533       errno = EVMSERR;
4534       vaxc$errno = status;
4535       return -1;
4536     }
4537
4538   return free_pages + frep0va + (0x7fffffff - frep1va);
4539 }
4540
4541 define_logical_name (varname, string)
4542      char *varname;
4543      char *string;
4544 {
4545   struct dsc$descriptor_s strdsc =
4546     {strlen (string), DSC$K_DTYPE_T, DSC$K_CLASS_S, string};
4547   struct dsc$descriptor_s envdsc =
4548     {strlen (varname), DSC$K_DTYPE_T, DSC$K_CLASS_S, varname};
4549   struct dsc$descriptor_s lnmdsc =
4550     {7, DSC$K_DTYPE_T, DSC$K_CLASS_S, "LNM$JOB"};
4551
4552   return LIB$SET_LOGICAL (&envdsc, &strdsc, &lnmdsc, 0, 0);
4553 }
4554
4555 delete_logical_name (varname)
4556      char *varname;
4557 {
4558   struct dsc$descriptor_s envdsc =
4559     {strlen (varname), DSC$K_DTYPE_T, DSC$K_CLASS_S, varname};
4560   struct dsc$descriptor_s lnmdsc =
4561     {7, DSC$K_DTYPE_T, DSC$K_CLASS_S, "LNM$JOB"};
4562
4563   return LIB$DELETE_LOGICAL (&envdsc, &lnmdsc);
4564 }
4565
4566 ulimit ()
4567 {}
4568
4569 setpgrp ()
4570 {}
4571
4572 execvp ()
4573 {
4574   error ("execvp system call not implemented");
4575 }
4576
4577 int
4578 rename (from, to)
4579      char *from, *to;
4580 {
4581   int status;
4582   struct FAB from_fab = cc$rms_fab, to_fab = cc$rms_fab;
4583   struct NAM from_nam = cc$rms_nam, to_nam = cc$rms_nam;
4584   char from_esn[NAM$C_MAXRSS];
4585   char to_esn[NAM$C_MAXRSS];
4586
4587   from_fab.fab$l_fna = from;
4588   from_fab.fab$b_fns = strlen (from);
4589   from_fab.fab$l_nam = &from_nam;
4590   from_fab.fab$l_fop = FAB$M_NAM;
4591
4592   from_nam.nam$l_esa = from_esn;
4593   from_nam.nam$b_ess = sizeof from_esn;
4594
4595   to_fab.fab$l_fna = to;
4596   to_fab.fab$b_fns = strlen (to);
4597   to_fab.fab$l_nam = &to_nam;
4598   to_fab.fab$l_fop = FAB$M_NAM;
4599
4600   to_nam.nam$l_esa = to_esn;
4601   to_nam.nam$b_ess = sizeof to_esn;
4602
4603   status = SYS$RENAME (&from_fab, 0, 0, &to_fab);
4604
4605   if (status & 1)
4606     return 0;
4607   else
4608     {
4609       if (status == RMS$_DEV)
4610         errno = EXDEV;
4611       else
4612         errno = EVMSERR;
4613       vaxc$errno = status;
4614       return -1;
4615     }
4616 }
4617
4618 /* This function renames a file like `rename', but it strips
4619    the version number from the "to" filename, such that the "to" file is
4620    will always be a new version.  It also sets the file protection once it is
4621    finished.  The protection that we will use is stored in fab_final_pro,
4622    and was set when we did a creat_copy_attrs to create the file that we
4623    are renaming.
4624
4625    We could use the chmod function, but Eunichs uses 3 bits per user category
4626    to describe the protection, and VMS uses 4 (write and delete are separate
4627    bits).  To maintain portability, the VMS implementation of `chmod' wires
4628    the W and D bits together.  */
4629
4630
4631 static struct fibdef fib;       /* We need this initialized to zero */
4632 char vms_file_written[NAM$C_MAXRSS];
4633
4634 int
4635 rename_sans_version (from,to)
4636      char *from, *to;
4637 {
4638   short int chan;
4639   int stat;
4640   short int iosb[4];
4641   int status;
4642   struct FAB to_fab = cc$rms_fab;
4643   struct NAM to_nam = cc$rms_nam;
4644   struct dsc$descriptor fib_d ={sizeof (fib),0,0,(char*) &fib};
4645   struct dsc$descriptor fib_attr[2]
4646     = {{sizeof (fab_final_pro),ATR$C_FPRO,0,(char*) &fab_final_pro},{0,0,0,0}};
4647   char to_esn[NAM$C_MAXRSS];
4648
4649   $DESCRIPTOR (disk,to_esn);
4650
4651   to_fab.fab$l_fna = to;
4652   to_fab.fab$b_fns = strlen (to);
4653   to_fab.fab$l_nam = &to_nam;
4654   to_fab.fab$l_fop = FAB$M_NAM;
4655
4656   to_nam.nam$l_esa = to_esn;
4657   to_nam.nam$b_ess = sizeof to_esn;
4658
4659   status = SYS$PARSE (&to_fab, 0, 0); /* figure out the full file name */
4660
4661   if (to_nam.nam$l_fnb && NAM$M_EXP_VER)
4662     *(to_nam.nam$l_ver) = '\0';
4663
4664   stat = rename (from, to_esn);
4665   if (stat < 0)
4666     return stat;
4667
4668   strcpy (vms_file_written, to_esn);
4669
4670   to_fab.fab$l_fna = vms_file_written; /* this points to the versionless name */
4671   to_fab.fab$b_fns = strlen (vms_file_written);
4672
4673   /* Now set the file protection to the correct value */
4674   SYS$OPEN (&to_fab, 0, 0);     /* This fills in the nam$w_fid fields */
4675
4676   /* Copy these fields into the fib */
4677   fib.fib$r_fid_overlay.fib$w_fid[0] = to_nam.nam$w_fid[0];
4678   fib.fib$r_fid_overlay.fib$w_fid[1] = to_nam.nam$w_fid[1];
4679   fib.fib$r_fid_overlay.fib$w_fid[2] = to_nam.nam$w_fid[2];
4680
4681   SYS$CLOSE (&to_fab, 0, 0);
4682
4683   stat = SYS$ASSIGN (&disk, &chan, 0, 0); /* open a channel to the disk */
4684   if (!stat)
4685     LIB$SIGNAL (stat);
4686   stat = SYS$QIOW (0, chan, IO$_MODIFY, iosb, 0, 0, &fib_d,
4687                    0, 0, 0, &fib_attr, 0);
4688   if (!stat)
4689     LIB$SIGNAL (stat);
4690   stat = SYS$DASSGN (chan);
4691   if (!stat)
4692     LIB$SIGNAL (stat);
4693   strcpy (vms_file_written, to_esn); /* We will write this to the terminal*/
4694   return 0;
4695 }
4696
4697 link (file, new)
4698      char * file, * new;
4699 {
4700   register status;
4701   struct FAB fab;
4702   struct NAM nam;
4703   unsigned short fid[3];
4704   char esa[NAM$C_MAXRSS];
4705
4706   fab = cc$rms_fab;
4707   fab.fab$l_fop = FAB$M_OFP;
4708   fab.fab$l_fna = file;
4709   fab.fab$b_fns = strlen (file);
4710   fab.fab$l_nam = &nam;
4711
4712   nam = cc$rms_nam;
4713   nam.nam$l_esa = esa;
4714   nam.nam$b_ess = NAM$C_MAXRSS;
4715
4716   status = SYS$PARSE (&fab);
4717   if ((status & 1) == 0)
4718     {
4719       errno = EVMSERR;
4720       vaxc$errno = status;
4721       return -1;
4722     }
4723   status = SYS$SEARCH (&fab);
4724   if ((status & 1) == 0)
4725     {
4726       errno = EVMSERR;
4727       vaxc$errno = status;
4728       return -1;
4729     }
4730
4731   fid[0] = nam.nam$w_fid[0];
4732   fid[1] = nam.nam$w_fid[1];
4733   fid[2] = nam.nam$w_fid[2];
4734
4735   fab.fab$l_fna = new;
4736   fab.fab$b_fns = strlen (new);
4737
4738   status = SYS$PARSE (&fab);
4739   if ((status & 1) == 0)
4740     {
4741       errno = EVMSERR;
4742       vaxc$errno = status;
4743       return -1;
4744     }
4745
4746   nam.nam$w_fid[0] = fid[0];
4747   nam.nam$w_fid[1] = fid[1];
4748   nam.nam$w_fid[2] = fid[2];
4749
4750   nam.nam$l_esa = nam.nam$l_name;
4751   nam.nam$b_esl = nam.nam$b_name + nam.nam$b_type + nam.nam$b_ver;
4752
4753   status = SYS$ENTER (&fab);
4754   if ((status & 1) == 0)
4755     {
4756       errno = EVMSERR;
4757       vaxc$errno = status;
4758       return -1;
4759     }
4760
4761   return 0;
4762 }
4763
4764 croak (badfunc)
4765      char *badfunc;
4766 {
4767   printf ("%s not yet implemented\r\n", badfunc);
4768   reset_sys_modes ();
4769   exit (1);
4770 }
4771
4772 long
4773 random ()
4774 {
4775   /* Arrange to return a range centered on zero.  */
4776   return rand () - (1 << 30);
4777 }
4778
4779 srandom (seed)
4780 {
4781   srand (seed);
4782 }
4783 #endif /* VMS */
4784 \f
4785 #ifdef AIX
4786
4787 /* Called from init_sys_modes.  */
4788 hft_init ()
4789 {
4790   int junk;
4791
4792   /* If we're not on an HFT we shouldn't do any of this.  We determine
4793      if we are on an HFT by trying to get an HFT error code.  If this
4794      call fails, we're not on an HFT. */
4795 #ifdef IBMR2AIX
4796   if (ioctl (0, HFQERROR, &junk) < 0)
4797     return;
4798 #else /* not IBMR2AIX */
4799   if (ioctl (0, HFQEIO, 0) < 0)
4800     return;
4801 #endif /* not IBMR2AIX */
4802
4803   /* On AIX the default hft keyboard mapping uses backspace rather than delete
4804      as the rubout key's ASCII code.  Here this is changed.  The bug is that
4805      there's no way to determine the old mapping, so in reset_sys_modes
4806      we need to assume that the normal map had been present.  Of course, this
4807      code also doesn't help if on a terminal emulator which doesn't understand
4808      HFT VTD's. */
4809   {
4810     struct hfbuf buf;
4811     struct hfkeymap keymap;
4812
4813     buf.hf_bufp = (char *)&keymap;
4814     buf.hf_buflen = sizeof (keymap);
4815     keymap.hf_nkeys = 2;
4816     keymap.hfkey[0].hf_kpos = 15;
4817     keymap.hfkey[0].hf_kstate = HFMAPCHAR | HFSHFNONE;
4818 #ifdef IBMR2AIX
4819     keymap.hfkey[0].hf_keyidh = '<';
4820 #else /* not IBMR2AIX */
4821     keymap.hfkey[0].hf_page = '<';
4822 #endif /* not IBMR2AIX */
4823     keymap.hfkey[0].hf_char = 127;
4824     keymap.hfkey[1].hf_kpos = 15;
4825     keymap.hfkey[1].hf_kstate = HFMAPCHAR | HFSHFSHFT;
4826 #ifdef IBMR2AIX
4827     keymap.hfkey[1].hf_keyidh = '<';
4828 #else /* not IBMR2AIX */
4829     keymap.hfkey[1].hf_page = '<';
4830 #endif /* not IBMR2AIX */
4831     keymap.hfkey[1].hf_char = 127;
4832     hftctl (0, HFSKBD, &buf);
4833   }
4834   /* The HFT system on AIX doesn't optimize for scrolling, so it's really ugly
4835      at times.  */
4836   line_ins_del_ok = char_ins_del_ok = 0;
4837 }
4838
4839 /* Reset the rubout key to backspace. */
4840
4841 hft_reset ()
4842 {
4843   struct hfbuf buf;
4844   struct hfkeymap keymap;
4845   int junk;
4846
4847 #ifdef IBMR2AIX
4848   if (ioctl (0, HFQERROR, &junk) < 0)
4849     return;
4850 #else /* not IBMR2AIX */
4851   if (ioctl (0, HFQEIO, 0) < 0)
4852     return;
4853 #endif /* not IBMR2AIX */
4854
4855   buf.hf_bufp = (char *)&keymap;
4856   buf.hf_buflen = sizeof (keymap);
4857   keymap.hf_nkeys = 2;
4858   keymap.hfkey[0].hf_kpos = 15;
4859   keymap.hfkey[0].hf_kstate = HFMAPCHAR | HFSHFNONE;
4860 #ifdef IBMR2AIX
4861   keymap.hfkey[0].hf_keyidh = '<';
4862 #else /* not IBMR2AIX */
4863   keymap.hfkey[0].hf_page = '<';
4864 #endif /* not IBMR2AIX */
4865   keymap.hfkey[0].hf_char = 8;
4866   keymap.hfkey[1].hf_kpos = 15;
4867   keymap.hfkey[1].hf_kstate = HFMAPCHAR | HFSHFSHFT;
4868 #ifdef IBMR2AIX
4869   keymap.hfkey[1].hf_keyidh = '<';
4870 #else /* not IBMR2AIX */
4871   keymap.hfkey[1].hf_page = '<';
4872 #endif /* not IBMR2AIX */
4873   keymap.hfkey[1].hf_char = 8;
4874   hftctl (0, HFSKBD, &buf);
4875 }
4876
4877 #endif /* AIX */
4878
4879 #ifdef USE_DL_STUBS
4880
4881 /* These are included on Sunos 4.1 when we do not use shared libraries.
4882    X11 libraries may refer to these functions but (we hope) do not
4883    actually call them.  */
4884
4885 void *
4886 dlopen ()
4887 {
4888   return 0;
4889 }
4890
4891 void *
4892 dlsym ()
4893 {
4894   return 0;
4895 }
4896
4897 int
4898 dlclose ()
4899 {
4900   return -1;
4901 }
4902
4903 #endif /* USE_DL_STUBS */
4904