gdb/thread.c

   1 /* Multi-process/thread control for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986, 1987, 1988, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   4    2000, 2001, 2002, 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
   5
   6    Contributed by Lynx Real-Time Systems, Inc.  Los Gatos, CA.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23 #include "defs.h"
  24 #include "symtab.h"
  25 #include "frame.h"
  26 #include "inferior.h"
  27 #include "environ.h"
  28 #include "value.h"
  29 #include "target.h"
  30 #include "gdbthread.h"
  31 #include "exceptions.h"
  32 #include "command.h"
  33 #include "gdbcmd.h"
  34 #include "regcache.h"
  35 #include "gdb.h"
  36 #include "gdb_string.h"
  37
  38 #include <ctype.h>
  39 #include <sys/types.h>
  40 #include <signal.h>
  41 #include "ui-out.h"
  42
  43 /* Definition of struct thread_info exported to gdbthread.h */
  44
  45 /* Prototypes for exported functions. */
  46
  47 void _initialize_thread (void);
  48
  49 /* Prototypes for local functions. */
  50
  51 static struct thread_info *thread_list = NULL;
  52 static int highest_thread_num;
  53
  54 static struct thread_info *find_thread_id (int num);
  55
  56 static void thread_command (char *tidstr, int from_tty);
  57 static void thread_apply_all_command (char *, int);
  58 static int thread_alive (struct thread_info *);
  59 static void info_threads_command (char *, int);
  60 static void thread_apply_command (char *, int);
  61 static void restore_current_thread (ptid_t);
  62 static void prune_threads (void);
  63 static struct cleanup *make_cleanup_restore_current_thread (ptid_t,
  64                                                             struct frame_id);
  65
  66 void
  67 delete_step_resume_breakpoint (void *arg)
  68 {
  69   struct breakpoint **breakpointp = (struct breakpoint **) arg;
  70   struct thread_info *tp;
  71
  72   if (*breakpointp != NULL)
  73     {
  74       delete_breakpoint (*breakpointp);
  75       for (tp = thread_list; tp; tp = tp->next)
  76         if (tp->step_resume_breakpoint == *breakpointp)
  77           tp->step_resume_breakpoint = NULL;
  78
  79       *breakpointp = NULL;
  80     }
  81 }
  82
  83 static void
  84 free_thread (struct thread_info *tp)
  85 {
  86   /* NOTE: this will take care of any left-over step_resume breakpoints,
  87      but not any user-specified thread-specific breakpoints.  We can not
  88      delete the breakpoint straight-off, because the inferior might not
  89      be stopped at the moment.  */
  90   if (tp->step_resume_breakpoint)
  91     tp->step_resume_breakpoint->disposition = disp_del_at_next_stop;
  92
  93   /* FIXME: do I ever need to call the back-end to give it a
  94      chance at this private data before deleting the thread?  */
  95   if (tp->private)
  96     xfree (tp->private);
  97
  98   xfree (tp);
  99 }
 100
 101 void
 102 init_thread_list (void)
 103 {
 104   struct thread_info *tp, *tpnext;
 105
 106   highest_thread_num = 0;
 107   if (!thread_list)
 108     return;
 109
 110   for (tp = thread_list; tp; tp = tpnext)
 111     {
 112       tpnext = tp->next;
 113       free_thread (tp);
 114     }
 115
 116   thread_list = NULL;
 117 }
 118
 119 /* add_thread now returns a pointer to the new thread_info,
 120    so that back_ends can initialize their private data.  */
 121
 122 struct thread_info *
 123 add_thread (ptid_t ptid)
 124 {
 125   struct thread_info *tp;
 126
 127   tp = (struct thread_info *) xmalloc (sizeof (*tp));
 128   memset (tp, 0, sizeof (*tp));
 129   tp->ptid = ptid;
 130   tp->num = ++highest_thread_num;
 131   tp->next = thread_list;
 132   thread_list = tp;
 133   return tp;
 134 }
 135
 136 void
 137 delete_thread (ptid_t ptid)
 138 {
 139   struct thread_info *tp, *tpprev;
 140
 141   tpprev = NULL;
 142
 143   for (tp = thread_list; tp; tpprev = tp, tp = tp->next)
 144     if (ptid_equal (tp->ptid, ptid))
 145       break;
 146
 147   if (!tp)
 148     return;
 149
 150   if (tpprev)
 151     tpprev->next = tp->next;
 152   else
 153     thread_list = tp->next;
 154
 155   free_thread (tp);
 156 }
 157
 158 static struct thread_info *
 159 find_thread_id (int num)
 160 {
 161   struct thread_info *tp;
 162
 163   for (tp = thread_list; tp; tp = tp->next)
 164     if (tp->num == num)
 165       return tp;
 166
 167   return NULL;
 168 }
 169
 170 /* Find a thread_info by matching PTID.  */
 171 struct thread_info *
 172 find_thread_pid (ptid_t ptid)
 173 {
 174   struct thread_info *tp;
 175
 176   for (tp = thread_list; tp; tp = tp->next)
 177     if (ptid_equal (tp->ptid, ptid))
 178       return tp;
 179
 180   return NULL;
 181 }
 182
 183 /*
 184  * Thread iterator function.
 185  *
 186  * Calls a callback function once for each thread, so long as
 187  * the callback function returns false.  If the callback function
 188  * returns true, the iteration will end and the current thread
 189  * will be returned.  This can be useful for implementing a
 190  * search for a thread with arbitrary attributes, or for applying
 191  * some operation to every thread.
 192  *
 193  * FIXME: some of the existing functionality, such as
 194  * "Thread apply all", might be rewritten using this functionality.
 195  */
 196
 197 struct thread_info *
 198 iterate_over_threads (int (*callback) (struct thread_info *, void *),
 199                       void *data)
 200 {
 201   struct thread_info *tp;
 202
 203   for (tp = thread_list; tp; tp = tp->next)
 204     if ((*callback) (tp, data))
 205       return tp;
 206
 207   return NULL;
 208 }
 209
 210 int
 211 valid_thread_id (int num)
 212 {
 213   struct thread_info *tp;
 214
 215   for (tp = thread_list; tp; tp = tp->next)
 216     if (tp->num == num)
 217       return 1;
 218
 219   return 0;
 220 }
 221
 222 int
 223 pid_to_thread_id (ptid_t ptid)
 224 {
 225   struct thread_info *tp;
 226
 227   for (tp = thread_list; tp; tp = tp->next)
 228     if (ptid_equal (tp->ptid, ptid))
 229       return tp->num;
 230
 231   return 0;
 232 }
 233
 234 ptid_t
 235 thread_id_to_pid (int num)
 236 {
 237   struct thread_info *thread = find_thread_id (num);
 238   if (thread)
 239     return thread->ptid;
 240   else
 241     return pid_to_ptid (-1);
 242 }
 243
 244 int
 245 in_thread_list (ptid_t ptid)
 246 {
 247   struct thread_info *tp;
 248
 249   for (tp = thread_list; tp; tp = tp->next)
 250     if (ptid_equal (tp->ptid, ptid))
 251       return 1;
 252
 253   return 0;                     /* Never heard of 'im */
 254 }
 255
 256 /* Print a list of thread ids currently known, and the total number of
 257    threads. To be used from within catch_errors. */
 258 static int
 259 do_captured_list_thread_ids (struct ui_out *uiout, void *arg)
 260 {
 261   struct thread_info *tp;
 262   int num = 0;
 263   struct cleanup *cleanup_chain;
 264
 265   prune_threads ();
 266   target_find_new_threads ();
 267
 268   cleanup_chain = make_cleanup_ui_out_tuple_begin_end (uiout, "thread-ids");
 269
 270   for (tp = thread_list; tp; tp = tp->next)
 271     {
 272       num++;
 273       ui_out_field_int (uiout, "thread-id", tp->num);
 274     }
 275
 276   do_cleanups (cleanup_chain);
 277   ui_out_field_int (uiout, "number-of-threads", num);
 278   return GDB_RC_OK;
 279 }
 280
 281 /* Official gdblib interface function to get a list of thread ids and
 282    the total number. */
 283 enum gdb_rc
 284 gdb_list_thread_ids (struct ui_out *uiout, char **error_message)
 285 {
 286   if (catch_exceptions_with_msg (uiout, do_captured_list_thread_ids, NULL,
 287                                  error_message, RETURN_MASK_ALL) < 0)
 288     return GDB_RC_FAIL;
 289   return GDB_RC_OK;
 290 }
 291
 292 /* Load infrun state for the thread PID.  */
 293
 294 void
 295 load_infrun_state (ptid_t ptid,
 296                    CORE_ADDR *prev_pc,
 297                    int *trap_expected,
 298                    struct breakpoint **step_resume_breakpoint,
 299                    CORE_ADDR *step_range_start,
 300                    CORE_ADDR *step_range_end,
 301                    struct frame_id *step_frame_id,
 302                    int *handling_longjmp,
 303                    int *stepping_over_breakpoint,
 304                    int *stepping_through_solib_after_catch,
 305                    bpstat *stepping_through_solib_catchpoints,
 306                    int *current_line,
 307                    struct symtab **current_symtab)
 308 {
 309   struct thread_info *tp;
 310
 311   /* If we can't find the thread, then we're debugging a single threaded
 312      process.  No need to do anything in that case.  */
 313   tp = find_thread_id (pid_to_thread_id (ptid));
 314   if (tp == NULL)
 315     return;
 316
 317   *prev_pc = tp->prev_pc;
 318   *trap_expected = tp->trap_expected;
 319   *step_resume_breakpoint = tp->step_resume_breakpoint;
 320   *step_range_start = tp->step_range_start;
 321   *step_range_end = tp->step_range_end;
 322   *step_frame_id = tp->step_frame_id;
 323   *handling_longjmp = tp->handling_longjmp;
 324   *stepping_over_breakpoint = tp->stepping_over_breakpoint;
 325   *stepping_through_solib_after_catch =
 326     tp->stepping_through_solib_after_catch;
 327   *stepping_through_solib_catchpoints =
 328     tp->stepping_through_solib_catchpoints;
 329   *current_line = tp->current_line;
 330   *current_symtab = tp->current_symtab;
 331 }
 332
 333 /* Save infrun state for the thread PID.  */
 334
 335 void
 336 save_infrun_state (ptid_t ptid,
 337                    CORE_ADDR prev_pc,
 338                    int trap_expected,
 339                    struct breakpoint *step_resume_breakpoint,
 340                    CORE_ADDR step_range_start,
 341                    CORE_ADDR step_range_end,
 342                    const struct frame_id *step_frame_id,
 343                    int handling_longjmp,
 344                    int stepping_over_breakpoint,
 345                    int stepping_through_solib_after_catch,
 346                    bpstat stepping_through_solib_catchpoints,
 347                    int current_line,
 348                    struct symtab *current_symtab)
 349 {
 350   struct thread_info *tp;
 351
 352   /* If we can't find the thread, then we're debugging a single-threaded
 353      process.  Nothing to do in that case.  */
 354   tp = find_thread_id (pid_to_thread_id (ptid));
 355   if (tp == NULL)
 356     return;
 357
 358   tp->prev_pc = prev_pc;
 359   tp->trap_expected = trap_expected;
 360   tp->step_resume_breakpoint = step_resume_breakpoint;
 361   tp->step_range_start = step_range_start;
 362   tp->step_range_end = step_range_end;
 363   tp->step_frame_id = (*step_frame_id);
 364   tp->handling_longjmp = handling_longjmp;
 365   tp->stepping_over_breakpoint = stepping_over_breakpoint;
 366   tp->stepping_through_solib_after_catch = stepping_through_solib_after_catch;
 367   tp->stepping_through_solib_catchpoints = stepping_through_solib_catchpoints;
 368   tp->current_line = current_line;
 369   tp->current_symtab = current_symtab;
 370 }
 371
 372 /* Return true if TP is an active thread. */
 373 static int
 374 thread_alive (struct thread_info *tp)
 375 {
 376   if (PIDGET (tp->ptid) == -1)
 377     return 0;
 378   if (!target_thread_alive (tp->ptid))
 379     {
 380       tp->ptid = pid_to_ptid (-1);      /* Mark it as dead */
 381       return 0;
 382     }
 383   return 1;
 384 }
 385
 386 static void
 387 prune_threads (void)
 388 {
 389   struct thread_info *tp, *next;
 390
 391   for (tp = thread_list; tp; tp = next)
 392     {
 393       next = tp->next;
 394       if (!thread_alive (tp))
 395         delete_thread (tp->ptid);
 396     }
 397 }
 398
 399 /* Print information about currently known threads
 400
 401  * Note: this has the drawback that it _really_ switches
 402  *       threads, which frees the frame cache.  A no-side
 403  *       effects info-threads command would be nicer.
 404  */
 405
 406 static void
 407 info_threads_command (char *arg, int from_tty)
 408 {
 409   struct thread_info *tp;
 410   ptid_t current_ptid;
 411   struct frame_info *cur_frame;
 412   struct cleanup *old_chain;
 413   struct frame_id saved_frame_id;
 414   char *extra_info;
 415
 416   /* Backup current thread and selected frame.  */
 417   saved_frame_id = get_frame_id (get_selected_frame (NULL));
 418   old_chain = make_cleanup_restore_current_thread (inferior_ptid, saved_frame_id);
 419
 420   prune_threads ();
 421   target_find_new_threads ();
 422   current_ptid = inferior_ptid;
 423   for (tp = thread_list; tp; tp = tp->next)
 424     {
 425       if (ptid_equal (tp->ptid, current_ptid))
 426         printf_filtered ("* ");
 427       else
 428         printf_filtered ("  ");
 429
 430       printf_filtered ("%d %s", tp->num, target_tid_to_str (tp->ptid));
 431
 432       extra_info = target_extra_thread_info (tp);
 433       if (extra_info)
 434         printf_filtered (" (%s)", extra_info);
 435       puts_filtered ("  ");
 436       /* That switch put us at the top of the stack (leaf frame).  */
 437       switch_to_thread (tp->ptid);
 438       print_stack_frame (get_selected_frame (NULL), 0, LOCATION);
 439     }
 440
 441   /* Restores the current thread and the frame selected before
 442      the "info threads" command.  */
 443   do_cleanups (old_chain);
 444
 445   /*  If case we were not able to find the original frame, print the
 446       new selected frame.  */
 447   if (frame_find_by_id (saved_frame_id) == NULL)
 448     {
 449       warning (_("Couldn't restore frame in current thread, at frame 0"));
 450       print_stack_frame (get_selected_frame (NULL), 0, LOCATION);
 451     }
 452 }
 453
 454 /* Switch from one thread to another. */
 455
 456 void
 457 switch_to_thread (ptid_t ptid)
 458 {
 459   if (ptid_equal (ptid, inferior_ptid))
 460     return;
 461
 462   inferior_ptid = ptid;
 463   reinit_frame_cache ();
 464   registers_changed ();
 465   stop_pc = read_pc ();
 466 }
 467
 468 static void
 469 restore_current_thread (ptid_t ptid)
 470 {
 471   if (!ptid_equal (ptid, inferior_ptid))
 472     {
 473       switch_to_thread (ptid);
 474     }
 475 }
 476
 477 static void
 478 restore_selected_frame (struct frame_id a_frame_id)
 479 {
 480   struct frame_info *selected_frame_info = NULL;
 481
 482   if (frame_id_eq (a_frame_id, null_frame_id))
 483     return;
 484
 485   if ((selected_frame_info = frame_find_by_id (a_frame_id)) != NULL)
 486     {
 487       select_frame (selected_frame_info);
 488     }
 489 }
 490
 491 struct current_thread_cleanup
 492 {
 493   ptid_t inferior_ptid;
 494   struct frame_id selected_frame_id;
 495 };
 496
 497 static void
 498 do_restore_current_thread_cleanup (void *arg)
 499 {
 500   struct current_thread_cleanup *old = arg;
 501   restore_current_thread (old->inferior_ptid);
 502   restore_selected_frame (old->selected_frame_id);
 503   xfree (old);
 504 }
 505
 506 static struct cleanup *
 507 make_cleanup_restore_current_thread (ptid_t inferior_ptid,
 508                                      struct frame_id a_frame_id)
 509 {
 510   struct current_thread_cleanup *old
 511     = xmalloc (sizeof (struct current_thread_cleanup));
 512   old->inferior_ptid = inferior_ptid;
 513   old->selected_frame_id = a_frame_id;
 514   return make_cleanup (do_restore_current_thread_cleanup, old);
 515 }
 516
 517 /* Apply a GDB command to a list of threads.  List syntax is a whitespace
 518    seperated list of numbers, or ranges, or the keyword `all'.  Ranges consist
 519    of two numbers seperated by a hyphen.  Examples:
 520
 521    thread apply 1 2 7 4 backtrace       Apply backtrace cmd to threads 1,2,7,4
 522    thread apply 2-7 9 p foo(1)  Apply p foo(1) cmd to threads 2->7 & 9
 523    thread apply all p x/i $pc   Apply x/i $pc cmd to all threads
 524  */
 525
 526 static void
 527 thread_apply_all_command (char *cmd, int from_tty)
 528 {
 529   struct thread_info *tp;
 530   struct cleanup *old_chain;
 531   struct cleanup *saved_cmd_cleanup_chain;
 532   char *saved_cmd;
 533   struct frame_id saved_frame_id;
 534   ptid_t current_ptid;
 535   int thread_has_changed = 0;
 536
 537   if (cmd == NULL || *cmd == '\000')
 538     error (_("Please specify a command following the thread ID list"));
 539
 540   current_ptid = inferior_ptid;
 541   saved_frame_id = get_frame_id (get_selected_frame (NULL));
 542   old_chain = make_cleanup_restore_current_thread (inferior_ptid, saved_frame_id);
 543
 544   /* It is safe to update the thread list now, before
 545      traversing it for "thread apply all".  MVS */
 546   target_find_new_threads ();
 547
 548   /* Save a copy of the command in case it is clobbered by
 549      execute_command */
 550   saved_cmd = xstrdup (cmd);
 551   saved_cmd_cleanup_chain = make_cleanup (xfree, (void *) saved_cmd);
 552   for (tp = thread_list; tp; tp = tp->next)
 553     if (thread_alive (tp))
 554       {
 555         switch_to_thread (tp->ptid);
 556         printf_filtered (_("\nThread %d (%s):\n"),
 557                          tp->num, target_tid_to_str (inferior_ptid));
 558         execute_command (cmd, from_tty);
 559         strcpy (cmd, saved_cmd);        /* Restore exact command used previously */
 560       }
 561
 562   if (!ptid_equal (current_ptid, inferior_ptid))
 563     thread_has_changed = 1;
 564
 565   do_cleanups (saved_cmd_cleanup_chain);
 566   do_cleanups (old_chain);
 567   /* Print stack frame only if we changed thread.  */
 568   if (thread_has_changed)
 569     print_stack_frame (get_current_frame (), 1, SRC_LINE);
 570
 571 }
 572
 573 static void
 574 thread_apply_command (char *tidlist, int from_tty)
 575 {
 576   char *cmd;
 577   char *p;
 578   struct cleanup *old_chain;
 579   struct cleanup *saved_cmd_cleanup_chain;
 580   char *saved_cmd;
 581   struct frame_id saved_frame_id;
 582   ptid_t current_ptid;
 583   int thread_has_changed = 0;
 584
 585   if (tidlist == NULL || *tidlist == '\000')
 586     error (_("Please specify a thread ID list"));
 587
 588   for (cmd = tidlist; *cmd != '\000' && !isalpha (*cmd); cmd++);
 589
 590   if (*cmd == '\000')
 591     error (_("Please specify a command following the thread ID list"));
 592
 593   current_ptid = inferior_ptid;
 594   saved_frame_id = get_frame_id (get_selected_frame (NULL));
 595   old_chain = make_cleanup_restore_current_thread (inferior_ptid, saved_frame_id);
 596
 597   /* Save a copy of the command in case it is clobbered by
 598      execute_command */
 599   saved_cmd = xstrdup (cmd);
 600   saved_cmd_cleanup_chain = make_cleanup (xfree, (void *) saved_cmd);
 601   while (tidlist < cmd)
 602     {
 603       struct thread_info *tp;
 604       int start, end;
 605
 606       start = strtol (tidlist, &p, 10);
 607       if (p == tidlist)
 608         error (_("Error parsing %s"), tidlist);
 609       tidlist = p;
 610
 611       while (*tidlist == ' ' || *tidlist == '\t')
 612         tidlist++;
 613
 614       if (*tidlist == '-')      /* Got a range of IDs? */
 615         {
 616           tidlist++;            /* Skip the - */
 617           end = strtol (tidlist, &p, 10);
 618           if (p == tidlist)
 619             error (_("Error parsing %s"), tidlist);
 620           tidlist = p;
 621
 622           while (*tidlist == ' ' || *tidlist == '\t')
 623             tidlist++;
 624         }
 625       else
 626         end = start;
 627
 628       for (; start <= end; start++)
 629         {
 630           tp = find_thread_id (start);
 631
 632           if (!tp)
 633             warning (_("Unknown thread %d."), start);
 634           else if (!thread_alive (tp))
 635             warning (_("Thread %d has terminated."), start);
 636           else
 637             {
 638               switch_to_thread (tp->ptid);
 639               printf_filtered (_("\nThread %d (%s):\n"), tp->num,
 640                                target_tid_to_str (inferior_ptid));
 641               execute_command (cmd, from_tty);
 642               strcpy (cmd, saved_cmd);  /* Restore exact command used previously */
 643             }
 644         }
 645     }
 646
 647   if (!ptid_equal (current_ptid, inferior_ptid))
 648     thread_has_changed = 1;
 649
 650   do_cleanups (saved_cmd_cleanup_chain);
 651   do_cleanups (old_chain);
 652   /* Print stack frame only if we changed thread.  */
 653   if (thread_has_changed)
 654     print_stack_frame (get_current_frame (), 1, SRC_LINE);
 655 }
 656
 657 /* Switch to the specified thread.  Will dispatch off to thread_apply_command
 658    if prefix of arg is `apply'.  */
 659
 660 static void
 661 thread_command (char *tidstr, int from_tty)
 662 {
 663   if (!tidstr)
 664     {
 665       /* Don't generate an error, just say which thread is current. */
 666       if (target_has_stack)
 667         printf_filtered (_("[Current thread is %d (%s)]\n"),
 668                          pid_to_thread_id (inferior_ptid),
 669                          target_tid_to_str (inferior_ptid));
 670       else
 671         error (_("No stack."));
 672       return;
 673     }
 674
 675   gdb_thread_select (uiout, tidstr, NULL);
 676 }
 677
 678 static int
 679 do_captured_thread_select (struct ui_out *uiout, void *tidstr)
 680 {
 681   int num;
 682   struct thread_info *tp;
 683
 684   num = value_as_long (parse_and_eval (tidstr));
 685
 686   tp = find_thread_id (num);
 687
 688   if (!tp)
 689     error (_("Thread ID %d not known."), num);
 690
 691   if (!thread_alive (tp))
 692     error (_("Thread ID %d has terminated."), num);
 693
 694   switch_to_thread (tp->ptid);
 695
 696   ui_out_text (uiout, "[Switching to thread ");
 697   ui_out_field_int (uiout, "new-thread-id", pid_to_thread_id (inferior_ptid));
 698   ui_out_text (uiout, " (");
 699   ui_out_text (uiout, target_tid_to_str (inferior_ptid));
 700   ui_out_text (uiout, ")]");
 701
 702   print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC);
 703   return GDB_RC_OK;
 704 }
 705
 706 enum gdb_rc
 707 gdb_thread_select (struct ui_out *uiout, char *tidstr, char **error_message)
 708 {
 709   if (catch_exceptions_with_msg (uiout, do_captured_thread_select, tidstr,
 710                                  error_message, RETURN_MASK_ALL) < 0)
 711     return GDB_RC_FAIL;
 712   return GDB_RC_OK;
 713 }
 714
 715 /* Commands with a prefix of `thread'.  */
 716 struct cmd_list_element *thread_cmd_list = NULL;
 717
 718 void
 719 _initialize_thread (void)
 720 {
 721   static struct cmd_list_element *thread_apply_list = NULL;
 722
 723   add_info ("threads", info_threads_command,
 724             _("IDs of currently known threads."));
 725
 726   add_prefix_cmd ("thread", class_run, thread_command, _("\
 727 Use this command to switch between threads.\n\
 728 The new thread ID must be currently known."),
 729                   &thread_cmd_list, "thread ", 1, &cmdlist);
 730
 731   add_prefix_cmd ("apply", class_run, thread_apply_command,
 732                   _("Apply a command to a list of threads."),
 733                   &thread_apply_list, "thread apply ", 1, &thread_cmd_list);
 734
 735   add_cmd ("all", class_run, thread_apply_all_command,
 736            _("Apply a command to all threads."), &thread_apply_list);
 737
 738   if (!xdb_commands)
 739     add_com_alias ("t", "thread", class_run, 1);
 740 }