libguile/simpos.c

   1 /*      Copyright (C) 1995,1996,1997,1998 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41
  42 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  43    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  44
  45 \f
  46
  47 #include <stdio.h>
  48 #include "_scm.h"
  49
  50 #include "scmsigs.h"
  51
  52 #include "scm_validate.h"
  53 #include "simpos.h"
  54
  55 #ifdef HAVE_STRING_H
  56 #include <string.h>
  57 #endif
  58 #ifdef HAVE_UNISTD_H
  59 #include <unistd.h>
  60 #endif
  61
  62 \f
  63 extern int system();
  64 \f
  65
  66 SCM_DEFINE(scm_system, "system", 0, 1, 0,
  67            (SCM cmd),
  68 "Executes @var{cmd} using the operating system's "command processor".
  69 Under Unix this is usually the default shell @code{sh}.  The value
  70 returned is @var{cmd}'s exit status as returned by @code{waitpid}, which
  71 can be interpreted using the functions above.
  72
  73 If @code{system} is called without arguments, it returns a boolean
  74 indicating whether the command processor is available.")
  75 #define FUNC_NAME s_scm_system
  76 {
  77   int rv;
  78
  79   if (SCM_UNBNDP (cmd))
  80     {
  81 #ifdef HAVE_SYSTEM
  82       rv = system (NULL);
  83 #else
  84       rv = 0;
  85 #endif
  86       return SCM_BOOL(rv);
  87     }
  88   SCM_VALIDATE_ROSTRING(1,cmd);
  89 #ifdef HAVE_SYSTEM
  90   SCM_DEFER_INTS;
  91   errno = 0;
  92   if (SCM_ROSTRINGP (cmd))
  93     cmd = scm_makfromstr (SCM_ROCHARS (cmd), SCM_ROLENGTH (cmd), 0);
  94   rv = system(SCM_ROCHARS(cmd));
  95   if (rv == -1 || (rv == 127 && errno != 0))
  96     SCM_SYSERROR;
  97   SCM_ALLOW_INTS;
  98   return SCM_MAKINUM (rv);
  99 #else
 100   SCM_SYSMISSING;
 101 #endif
 102 }
 103 #undef FUNC_NAME
 104
 105 extern char *getenv();
 106 SCM_DEFINE (scm_getenv, "getenv", 1, 0, 0,
 107             (SCM nam),
 108 "Looks up the string @var{name} in the current environment.  The return
 109 value is @code{#f} unless a string of the form @code{NAME=VALUE} is
 110 found, in which case the string @code{VALUE} is
 111 returned.")
 112 #define FUNC_NAME s_scm_getenv
 113 {
 114   char *val;
 115   SCM_VALIDATE_ROSTRING(1,nam);
 116   nam = scm_makfromstr (SCM_ROCHARS (nam), SCM_ROLENGTH (nam), 0);
 117   val = getenv(SCM_CHARS(nam));
 118   return (val) ? scm_makfromstr(val, (scm_sizet)strlen(val), 0) : SCM_BOOL_F;
 119 }
 120 #undef FUNC_NAME
 121
 122 /* simple exit, without unwinding the scheme stack or flushing ports.  */
 123 SCM_DEFINE (scm_primitive_exit, "primitive-exit", 0, 1, 0,
 124             (SCM status),
 125 "Terminate the current process without unwinding the Scheme stack.
 126 This is would typically be useful after a fork.  The exit status
 127 is @var{status} if supplied, otherwise zero.")
 128 #define FUNC_NAME s_scm_primitive_exit
 129 {
 130   int cstatus = 0;
 131   if (!SCM_UNBNDP (status))
 132     {
 133       SCM_VALIDATE_INUM(1,status);
 134       cstatus = SCM_INUM (status);
 135     }
 136   exit (cstatus);
 137 }
 138 #undef FUNC_NAME
 139
 140
 141 void
 142 scm_init_simpos ()
 143 {
 144 #include "simpos.x"
 145 }
 146