| 1 | /* Session management module for systems which understand the X Session |
| 2 | management protocol. |
| 3 | Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008 |
| 4 | Free Software Foundation, Inc. |
| 5 | |
| 6 | This file is part of GNU Emacs. |
| 7 | |
| 8 | GNU Emacs is free software: you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation, either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | GNU Emacs is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include <config.h> |
| 22 | |
| 23 | #ifdef HAVE_X_SM |
| 24 | |
| 25 | #include <X11/SM/SMlib.h> |
| 26 | #include <X11/Xlib.h> |
| 27 | #include <X11/Xutil.h> |
| 28 | |
| 29 | #ifdef HAVE_UNISTD_H |
| 30 | #include <unistd.h> |
| 31 | #endif |
| 32 | |
| 33 | #include <sys/param.h> |
| 34 | #include <stdio.h> |
| 35 | |
| 36 | #include "lisp.h" |
| 37 | #include "systime.h" |
| 38 | #include "sysselect.h" |
| 39 | #include "frame.h" |
| 40 | #include "termhooks.h" |
| 41 | #include "termopts.h" |
| 42 | #include "xterm.h" |
| 43 | |
| 44 | /* The user login name. */ |
| 45 | |
| 46 | extern Lisp_Object Vuser_login_name; |
| 47 | |
| 48 | /* This is the event used when SAVE_SESSION_EVENT occurs. */ |
| 49 | |
| 50 | static struct input_event emacs_event; |
| 51 | |
| 52 | /* The descriptor that we use to check for data from the session manager. */ |
| 53 | |
| 54 | static int ice_fd = -1; |
| 55 | |
| 56 | /* A flag that says if we are in shutdown interactions or not. */ |
| 57 | |
| 58 | static int doing_interact = False; |
| 59 | |
| 60 | /* The session manager object for the session manager connection. */ |
| 61 | |
| 62 | static SmcConn smc_conn; |
| 63 | |
| 64 | /* The client session id for this session. */ |
| 65 | |
| 66 | static char *client_id; |
| 67 | |
| 68 | /* The full path name to the Emacs program. */ |
| 69 | |
| 70 | static char *emacs_program; |
| 71 | |
| 72 | /* The client session id for this session as a lisp object. */ |
| 73 | |
| 74 | Lisp_Object Vx_session_id; |
| 75 | |
| 76 | /* The id we had the previous session. This is only available if we |
| 77 | have been started by the session manager with SMID_OPT. */ |
| 78 | |
| 79 | Lisp_Object Vx_session_previous_id; |
| 80 | |
| 81 | /* The option we tell the session manager to start Emacs with when |
| 82 | restarting Emacs. The client_id is appended. */ |
| 83 | |
| 84 | #define SMID_OPT "--smid=" |
| 85 | |
| 86 | |
| 87 | /* The option to start Emacs without the splash screen when |
| 88 | restarting Emacs. */ |
| 89 | |
| 90 | #define NOSPLASH_OPT "--no-splash" |
| 91 | |
| 92 | |
| 93 | /* Handle any messages from the session manager. If no connection is |
| 94 | open to a session manager, just return 0. |
| 95 | Otherwise returns 1 if SAVE_SESSION_EVENT is stored in buffer BUFP. */ |
| 96 | |
| 97 | int |
| 98 | x_session_check_input (bufp) |
| 99 | struct input_event *bufp; |
| 100 | { |
| 101 | SELECT_TYPE read_fds; |
| 102 | EMACS_TIME tmout; |
| 103 | |
| 104 | if (ice_fd == -1) return 0; |
| 105 | |
| 106 | FD_ZERO (&read_fds); |
| 107 | FD_SET (ice_fd, &read_fds); |
| 108 | |
| 109 | tmout.tv_sec = 0; |
| 110 | tmout.tv_usec = 0; |
| 111 | |
| 112 | /* Reset this so wo can check kind after callbacks have been called by |
| 113 | IceProcessMessages. The smc_interact_CB sets the kind to |
| 114 | SAVE_SESSION_EVENT, but we don't know beforehand if that callback |
| 115 | will be called. */ |
| 116 | emacs_event.kind = NO_EVENT; |
| 117 | |
| 118 | if (select (ice_fd+1, &read_fds, |
| 119 | (SELECT_TYPE *)0, (SELECT_TYPE *)0, &tmout) < 0) |
| 120 | { |
| 121 | ice_fd = -1; |
| 122 | return 0; |
| 123 | } |
| 124 | |
| 125 | |
| 126 | if (FD_ISSET (ice_fd, &read_fds)) |
| 127 | IceProcessMessages (SmcGetIceConnection (smc_conn), |
| 128 | (IceReplyWaitInfo *)0, (Bool *)0); |
| 129 | |
| 130 | |
| 131 | /* Check if smc_interact_CB was called and we shall generate a |
| 132 | SAVE_SESSION_EVENT. */ |
| 133 | if (emacs_event.kind == NO_EVENT) |
| 134 | return 0; |
| 135 | |
| 136 | bcopy (&emacs_event, bufp, sizeof (struct input_event)); |
| 137 | return 1; |
| 138 | } |
| 139 | |
| 140 | /* Return non-zero if we have a connection to a session manager. */ |
| 141 | |
| 142 | int |
| 143 | x_session_have_connection () |
| 144 | { |
| 145 | return ice_fd != -1; |
| 146 | } |
| 147 | |
| 148 | /* This is called when the session manager says it is OK to interact with the |
| 149 | user. Here we set the kind to SAVE_SESSION_EVENT so an event is generated. |
| 150 | Then lisp code can interact with the user. */ |
| 151 | |
| 152 | static void |
| 153 | smc_interact_CB (smcConn, clientData) |
| 154 | SmcConn smcConn; |
| 155 | SmPointer clientData; |
| 156 | { |
| 157 | doing_interact = True; |
| 158 | emacs_event.kind = SAVE_SESSION_EVENT; |
| 159 | } |
| 160 | |
| 161 | /* This is called when the session manager tells us to save ourselves. |
| 162 | We set the required properties so the session manager can restart us, |
| 163 | plus the current working directory property (not mandatory) so we |
| 164 | are started in the correct directory. |
| 165 | |
| 166 | If this is a shutdown and we can request to interact with the user, |
| 167 | we do so, because we don't know what the lisp code might do. */ |
| 168 | |
| 169 | static void |
| 170 | smc_save_yourself_CB (smcConn, |
| 171 | clientData, |
| 172 | saveType, |
| 173 | shutdown, |
| 174 | interactStyle, |
| 175 | fast) |
| 176 | SmcConn smcConn; |
| 177 | SmPointer clientData; |
| 178 | int saveType; |
| 179 | Bool shutdown; |
| 180 | int interactStyle; |
| 181 | Bool fast; |
| 182 | { |
| 183 | #define NR_PROPS 5 |
| 184 | |
| 185 | SmProp *props[NR_PROPS]; |
| 186 | SmProp prop_ptr[NR_PROPS]; |
| 187 | |
| 188 | SmPropValue values[20]; |
| 189 | int val_idx = 0; |
| 190 | int props_idx = 0; |
| 191 | |
| 192 | char *cwd = NULL; |
| 193 | char *smid_opt; |
| 194 | |
| 195 | /* How to start a new instance of Emacs. */ |
| 196 | props[props_idx] = &prop_ptr[props_idx]; |
| 197 | props[props_idx]->name = SmCloneCommand; |
| 198 | props[props_idx]->type = SmLISTofARRAY8; |
| 199 | props[props_idx]->num_vals = 1; |
| 200 | props[props_idx]->vals = &values[val_idx++]; |
| 201 | props[props_idx]->vals[0].length = strlen (emacs_program); |
| 202 | props[props_idx]->vals[0].value = emacs_program; |
| 203 | ++props_idx; |
| 204 | |
| 205 | /* The name of the program. */ |
| 206 | props[props_idx] = &prop_ptr[props_idx]; |
| 207 | props[props_idx]->name = SmProgram; |
| 208 | props[props_idx]->type = SmARRAY8; |
| 209 | props[props_idx]->num_vals = 1; |
| 210 | props[props_idx]->vals = &values[val_idx++]; |
| 211 | props[props_idx]->vals[0].length = strlen (SDATA (Vinvocation_name)); |
| 212 | props[props_idx]->vals[0].value = SDATA (Vinvocation_name); |
| 213 | ++props_idx; |
| 214 | |
| 215 | /* How to restart Emacs (i.e.: /path/to/emacs --smid=xxxx --no-splash). */ |
| 216 | props[props_idx] = &prop_ptr[props_idx]; |
| 217 | props[props_idx]->name = SmRestartCommand; |
| 218 | props[props_idx]->type = SmLISTofARRAY8; |
| 219 | props[props_idx]->num_vals = 3; /* /path/to/emacs, --smid=xxx --no-splash */ |
| 220 | props[props_idx]->vals = &values[val_idx]; |
| 221 | props[props_idx]->vals[0].length = strlen (emacs_program); |
| 222 | props[props_idx]->vals[0].value = emacs_program; |
| 223 | |
| 224 | smid_opt = xmalloc (strlen (SMID_OPT) + strlen (client_id) + 1); |
| 225 | strcpy (smid_opt, SMID_OPT); |
| 226 | strcat (smid_opt, client_id); |
| 227 | |
| 228 | props[props_idx]->vals[1].length = strlen (smid_opt); |
| 229 | props[props_idx]->vals[1].value = smid_opt; |
| 230 | |
| 231 | props[props_idx]->vals[2].length = strlen (NOSPLASH_OPT); |
| 232 | props[props_idx]->vals[2].value = NOSPLASH_OPT; |
| 233 | val_idx += 3; |
| 234 | ++props_idx; |
| 235 | |
| 236 | /* User id. */ |
| 237 | props[props_idx] = &prop_ptr[props_idx]; |
| 238 | props[props_idx]->name = SmUserID; |
| 239 | props[props_idx]->type = SmARRAY8; |
| 240 | props[props_idx]->num_vals = 1; |
| 241 | props[props_idx]->vals = &values[val_idx++]; |
| 242 | props[props_idx]->vals[0].length = strlen (SDATA (Vuser_login_name)); |
| 243 | props[props_idx]->vals[0].value = SDATA (Vuser_login_name); |
| 244 | ++props_idx; |
| 245 | |
| 246 | cwd = get_current_dir_name (); |
| 247 | |
| 248 | if (cwd) |
| 249 | { |
| 250 | props[props_idx] = &prop_ptr[props_idx]; |
| 251 | props[props_idx]->name = SmCurrentDirectory; |
| 252 | props[props_idx]->type = SmARRAY8; |
| 253 | props[props_idx]->num_vals = 1; |
| 254 | props[props_idx]->vals = &values[val_idx++]; |
| 255 | props[props_idx]->vals[0].length = strlen (cwd); |
| 256 | props[props_idx]->vals[0].value = cwd; |
| 257 | ++props_idx; |
| 258 | } |
| 259 | |
| 260 | |
| 261 | SmcSetProperties (smcConn, props_idx, props); |
| 262 | |
| 263 | xfree (smid_opt); |
| 264 | |
| 265 | free (cwd); |
| 266 | |
| 267 | /* See if we maybe shall interact with the user. */ |
| 268 | if (interactStyle != SmInteractStyleAny |
| 269 | || ! shutdown |
| 270 | || saveType == SmSaveLocal |
| 271 | || ! SmcInteractRequest (smcConn, SmDialogNormal, smc_interact_CB, 0)) |
| 272 | { |
| 273 | /* No interaction, we are done saving ourself. */ |
| 274 | SmcSaveYourselfDone (smcConn, True); |
| 275 | } |
| 276 | } |
| 277 | |
| 278 | /* According to the SM specification, this shall close the connection. */ |
| 279 | |
| 280 | static void |
| 281 | smc_die_CB (smcConn, clientData) |
| 282 | SmcConn smcConn; |
| 283 | SmPointer clientData; |
| 284 | { |
| 285 | SmcCloseConnection (smcConn, 0, 0); |
| 286 | ice_fd = -1; |
| 287 | } |
| 288 | |
| 289 | /* We don't use the next two but they are mandatory, leave them empty. |
| 290 | According to the SM specification, we should not interact with the |
| 291 | user between smc_save_yourself_CB is called and until smc_save_complete_CB |
| 292 | is called. It seems like a lot of job to implement this and it doesn't |
| 293 | even seem necessary. */ |
| 294 | |
| 295 | static void |
| 296 | smc_save_complete_CB (smcConn, clientData) |
| 297 | SmcConn smcConn; |
| 298 | SmPointer clientData; |
| 299 | { |
| 300 | /* Empty */ |
| 301 | } |
| 302 | |
| 303 | static void |
| 304 | smc_shutdown_cancelled_CB (smcConn, clientData) |
| 305 | SmcConn smcConn; |
| 306 | SmPointer clientData; |
| 307 | { |
| 308 | /* Empty */ |
| 309 | } |
| 310 | |
| 311 | /* Error handlers for SM and ICE. We don't want to exit Emacs just |
| 312 | because there is some error in the session management. */ |
| 313 | |
| 314 | static void |
| 315 | smc_error_handler (smcConn, |
| 316 | swap, |
| 317 | offendingMinorOpcode, |
| 318 | offendingSequence, |
| 319 | errorClass, |
| 320 | severity, |
| 321 | values) |
| 322 | SmcConn smcConn; |
| 323 | Bool swap; |
| 324 | int offendingMinorOpcode; |
| 325 | unsigned long offendingSequence; |
| 326 | int errorClass; |
| 327 | int severity; |
| 328 | SmPointer values; |
| 329 | { |
| 330 | /* Empty */ |
| 331 | } |
| 332 | |
| 333 | static void |
| 334 | ice_error_handler (iceConn, |
| 335 | swap, |
| 336 | offendingMinorOpcode, |
| 337 | offendingSequence, |
| 338 | errorClass, |
| 339 | severity, |
| 340 | values) |
| 341 | IceConn iceConn; |
| 342 | Bool swap; |
| 343 | int offendingMinorOpcode; |
| 344 | unsigned long offendingSequence; |
| 345 | int errorClass; |
| 346 | int severity; |
| 347 | IcePointer values; |
| 348 | { |
| 349 | /* Empty */ |
| 350 | } |
| 351 | |
| 352 | |
| 353 | static void |
| 354 | ice_io_error_handler (iceConn) |
| 355 | IceConn iceConn; |
| 356 | { |
| 357 | /* Connection probably gone. */ |
| 358 | ice_fd = -1; |
| 359 | } |
| 360 | |
| 361 | /* This is called when the ICE connection is created or closed. The SM library |
| 362 | uses ICE as it transport protocol. */ |
| 363 | |
| 364 | static void |
| 365 | ice_conn_watch_CB (iceConn, clientData, opening, watchData) |
| 366 | IceConn iceConn; |
| 367 | IcePointer clientData; |
| 368 | Bool opening; |
| 369 | IcePointer *watchData; |
| 370 | { |
| 371 | if (! opening) |
| 372 | { |
| 373 | ice_fd = -1; |
| 374 | return; |
| 375 | } |
| 376 | |
| 377 | ice_fd = IceConnectionNumber (iceConn); |
| 378 | #ifdef F_SETOWN |
| 379 | fcntl (ice_fd, F_SETOWN, getpid ()); |
| 380 | #endif /* ! defined (F_SETOWN) */ |
| 381 | |
| 382 | #ifdef SIGIO |
| 383 | if (interrupt_input) |
| 384 | init_sigio (ice_fd); |
| 385 | #endif /* ! defined (SIGIO) */ |
| 386 | } |
| 387 | |
| 388 | /* Create the client leader window. */ |
| 389 | |
| 390 | static void |
| 391 | create_client_leader_window (dpyinfo, client_id) |
| 392 | struct x_display_info *dpyinfo; |
| 393 | char *client_id; |
| 394 | { |
| 395 | Window w; |
| 396 | XClassHint class_hints; |
| 397 | Atom sm_id; |
| 398 | |
| 399 | w = XCreateSimpleWindow (dpyinfo->display, |
| 400 | dpyinfo->root_window, |
| 401 | -1, -1, 1, 1, |
| 402 | CopyFromParent, CopyFromParent, CopyFromParent); |
| 403 | |
| 404 | class_hints.res_name = (char *) SDATA (Vx_resource_name); |
| 405 | class_hints.res_class = (char *) SDATA (Vx_resource_class); |
| 406 | XSetClassHint (dpyinfo->display, w, &class_hints); |
| 407 | XStoreName (dpyinfo->display, w, class_hints.res_name); |
| 408 | |
| 409 | sm_id = XInternAtom (dpyinfo->display, "SM_CLIENT_ID", False); |
| 410 | XChangeProperty (dpyinfo->display, w, sm_id, XA_STRING, 8, PropModeReplace, |
| 411 | client_id, strlen (client_id)); |
| 412 | |
| 413 | dpyinfo->client_leader_window = w; |
| 414 | } |
| 415 | |
| 416 | /* Try to open a connection to the session manager. */ |
| 417 | |
| 418 | void |
| 419 | x_session_initialize (dpyinfo) |
| 420 | struct x_display_info *dpyinfo; |
| 421 | { |
| 422 | #define SM_ERRORSTRING_LEN 512 |
| 423 | char errorstring[SM_ERRORSTRING_LEN]; |
| 424 | char* previous_id = NULL; |
| 425 | SmcCallbacks callbacks; |
| 426 | int name_len = 0; |
| 427 | |
| 428 | /* Check if we where started by the session manager. If so, we will |
| 429 | have a previous id. */ |
| 430 | if (! EQ (Vx_session_previous_id, Qnil) && STRINGP (Vx_session_previous_id)) |
| 431 | previous_id = SDATA (Vx_session_previous_id); |
| 432 | |
| 433 | /* Construct the path to the Emacs program. */ |
| 434 | if (! EQ (Vinvocation_directory, Qnil)) |
| 435 | name_len += strlen (SDATA (Vinvocation_directory)); |
| 436 | name_len += strlen (SDATA (Vinvocation_name)); |
| 437 | |
| 438 | /* This malloc will not be freed, but it is only done once, and hopefully |
| 439 | not very large */ |
| 440 | emacs_program = xmalloc (name_len + 1); |
| 441 | emacs_program[0] = '\0'; |
| 442 | |
| 443 | if (! EQ (Vinvocation_directory, Qnil)) |
| 444 | strcpy (emacs_program, SDATA (Vinvocation_directory)); |
| 445 | strcat (emacs_program, SDATA (Vinvocation_name)); |
| 446 | |
| 447 | /* The SM protocol says all callbacks are mandatory, so set up all |
| 448 | here and in the mask passed to SmcOpenConnection. */ |
| 449 | callbacks.save_yourself.callback = smc_save_yourself_CB; |
| 450 | callbacks.save_yourself.client_data = 0; |
| 451 | callbacks.die.callback = smc_die_CB; |
| 452 | callbacks.die.client_data = 0; |
| 453 | callbacks.save_complete.callback = smc_save_complete_CB; |
| 454 | callbacks.save_complete.client_data = 0; |
| 455 | callbacks.shutdown_cancelled.callback = smc_shutdown_cancelled_CB; |
| 456 | callbacks.shutdown_cancelled.client_data = 0; |
| 457 | |
| 458 | /* Set error handlers. */ |
| 459 | SmcSetErrorHandler (smc_error_handler); |
| 460 | IceSetErrorHandler (ice_error_handler); |
| 461 | IceSetIOErrorHandler (ice_io_error_handler); |
| 462 | |
| 463 | /* Install callback for when connection status changes. */ |
| 464 | IceAddConnectionWatch (ice_conn_watch_CB, 0); |
| 465 | |
| 466 | /* Open the connection to the session manager. A failure is not |
| 467 | critical, it usually means that no session manager is running. |
| 468 | The errorstring is here for debugging. */ |
| 469 | smc_conn = SmcOpenConnection (NULL, NULL, 1, 0, |
| 470 | (SmcSaveYourselfProcMask| |
| 471 | SmcDieProcMask| |
| 472 | SmcSaveCompleteProcMask| |
| 473 | SmcShutdownCancelledProcMask), |
| 474 | &callbacks, |
| 475 | previous_id, |
| 476 | &client_id, |
| 477 | SM_ERRORSTRING_LEN, |
| 478 | errorstring); |
| 479 | |
| 480 | if (smc_conn != 0) |
| 481 | { |
| 482 | Vx_session_id = make_string (client_id, strlen (client_id)); |
| 483 | |
| 484 | #ifdef USE_GTK |
| 485 | /* GTK creats a leader window by itself, but we need to tell |
| 486 | it about our client_id. */ |
| 487 | gdk_set_sm_client_id (client_id); |
| 488 | #else |
| 489 | create_client_leader_window (dpyinfo, client_id); |
| 490 | #endif |
| 491 | } |
| 492 | } |
| 493 | |
| 494 | /* Ensure that the session manager is not contacted again. */ |
| 495 | |
| 496 | void |
| 497 | x_session_close () |
| 498 | { |
| 499 | ice_fd = -1; |
| 500 | } |
| 501 | |
| 502 | |
| 503 | DEFUN ("handle-save-session", Fhandle_save_session, |
| 504 | Shandle_save_session, 1, 1, "e", |
| 505 | doc: /* Handle the save_yourself event from a session manager. |
| 506 | A session manager can tell Emacs that the window system is shutting down |
| 507 | by sending Emacs a save_yourself message. Emacs executes this function when |
| 508 | such an event occurs. This function then executes `emacs-session-save'. |
| 509 | After that, this function informs the session manager that it can continue |
| 510 | or abort shutting down the window system depending on the return value |
| 511 | from `emacs-session-save' If the return value is non-nil the session manager |
| 512 | is told to abort the window system shutdown. |
| 513 | |
| 514 | Do not call this function yourself. */) |
| 515 | (event) |
| 516 | Lisp_Object event; |
| 517 | { |
| 518 | /* Check doing_interact so that we don't do anything if someone called |
| 519 | this at the wrong time. */ |
| 520 | if (doing_interact) |
| 521 | { |
| 522 | Bool cancel_shutdown = False; |
| 523 | |
| 524 | cancel_shutdown = ! EQ (call0 (intern ("emacs-session-save")), Qnil); |
| 525 | |
| 526 | SmcInteractDone (smc_conn, cancel_shutdown); |
| 527 | SmcSaveYourselfDone (smc_conn, True); |
| 528 | |
| 529 | doing_interact = False; |
| 530 | } |
| 531 | |
| 532 | return Qnil; |
| 533 | } |
| 534 | |
| 535 | \f |
| 536 | /*********************************************************************** |
| 537 | Initialization |
| 538 | ***********************************************************************/ |
| 539 | void |
| 540 | syms_of_xsmfns () |
| 541 | { |
| 542 | DEFVAR_LISP ("x-session-id", &Vx_session_id, |
| 543 | doc: /* The session id Emacs got from the session manager for this session. |
| 544 | Changing the value does not change the session id used by Emacs. |
| 545 | The value is nil if no session manager is running. |
| 546 | See also `x-session-previous-id', `emacs-save-session-functions', |
| 547 | `emacs-session-save' and `emacs-session-restore'." */); |
| 548 | Vx_session_id = Qnil; |
| 549 | |
| 550 | DEFVAR_LISP ("x-session-previous-id", &Vx_session_previous_id, |
| 551 | doc: /* The previous session id Emacs got from session manager. |
| 552 | If Emacs is running on a window system that has a session manager, the |
| 553 | session manager gives Emacs a session id. It is feasible for Emacs Lisp |
| 554 | code to use the session id to save configuration in, for example, a file |
| 555 | with a file name based on the session id. If Emacs is running when the |
| 556 | window system is shut down, the session manager remembers that Emacs was |
| 557 | running and saves the session id Emacs had. |
| 558 | |
| 559 | When the window system is started again, the session manager restarts |
| 560 | Emacs and hands Emacs the session id it had the last time it was |
| 561 | running. This is now the previous session id and the value of this |
| 562 | variable. If configuration was saved in a file as stated above, the |
| 563 | previous session id shall be used to reconstruct the file name. |
| 564 | |
| 565 | The session id Emacs has while it is running is in the variable |
| 566 | `x-session-id'. The value of this variable and `x-session-id' may be the |
| 567 | same, depending on how the session manager works. |
| 568 | |
| 569 | See also `emacs-save-session-functions', `emacs-session-save' and |
| 570 | `emacs-session-restore'." */); |
| 571 | Vx_session_previous_id = Qnil; |
| 572 | |
| 573 | defsubr (&Shandle_save_session); |
| 574 | } |
| 575 | |
| 576 | #endif /* HAVE_X_SM */ |
| 577 | |
| 578 | /* arch-tag: 56a2c58c-adfa-430a-b772-130abd29fd2e |
| 579 | (do not change this comment) */ |