gdb/thread.c

   1 /* Multi-process/thread control for GDB, the GNU debugger.
   2    Copyright 1986, 1987, 1988, 1993, 1998, 1999, 2000
   3
   4    Contributed by Lynx Real-Time Systems, Inc.  Los Gatos, CA.
   5    Free Software Foundation, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330,
  22    Boston, MA 02111-1307, USA.  */
  23
  24 #include "defs.h"
  25 #include "symtab.h"
  26 #include "frame.h"
  27 #include "inferior.h"
  28 #include "environ.h"
  29 #include "value.h"
  30 #include "target.h"
  31 #include "gdbthread.h"
  32 #include "command.h"
  33 #include "gdbcmd.h"
  34
  35 #include <ctype.h>
  36 #include <sys/types.h>
  37 #include <signal.h>
  38 #ifdef UI_OUT
  39 #include "ui-out.h"
  40 #endif
  41
  42 /*#include "lynxos-core.h" */
  43
  44 /* Definition of struct thread_info exported to gdbthread.h */
  45
  46 /* Prototypes for exported functions. */
  47
  48 void _initialize_thread (void);
  49
  50 /* Prototypes for local functions. */
  51
  52 static struct thread_info *thread_list = NULL;
  53 static int highest_thread_num;
  54
  55 static struct thread_info *find_thread_id (int num);
  56
  57 static void thread_command (char *tidstr, int from_tty);
  58 static void thread_apply_all_command (char *, int);
  59 static int thread_alive (struct thread_info *);
  60 static void info_threads_command (char *, int);
  61 static void thread_apply_command (char *, int);
  62 static void restore_current_thread (int);
  63 static void switch_to_thread (int pid);
  64 static void prune_threads (void);
  65
  66 void
  67 init_thread_list ()
  68 {
  69   struct thread_info *tp, *tpnext;
  70
  71   if (!thread_list)
  72     return;
  73
  74   for (tp = thread_list; tp; tp = tpnext)
  75     {
  76       tpnext = tp->next;
  77       free (tp);
  78     }
  79
  80   thread_list = NULL;
  81   highest_thread_num = 0;
  82 }
  83
  84 /* add_thread now returns a pointer to the new thread_info,
  85    so that back_ends can initialize their private data.  */
  86
  87 struct thread_info *
  88 add_thread (pid)
  89      int pid;
  90 {
  91   struct thread_info *tp;
  92
  93   tp = (struct thread_info *) xmalloc (sizeof (struct thread_info));
  94
  95   tp->pid = pid;
  96   tp->num = ++highest_thread_num;
  97   tp->prev_pc = 0;
  98   tp->prev_func_start = 0;
  99   tp->prev_func_name = NULL;
 100   tp->step_range_start = 0;
 101   tp->step_range_end = 0;
 102   tp->step_frame_address = 0;
 103   tp->step_resume_breakpoint = 0;
 104   tp->through_sigtramp_breakpoint = 0;
 105   tp->handling_longjmp = 0;
 106   tp->trap_expected = 0;
 107   tp->another_trap = 0;
 108   tp->stepping_through_solib_after_catch = 0;
 109   tp->stepping_through_solib_catchpoints = NULL;
 110   tp->stepping_through_sigtramp = 0;
 111   tp->next = thread_list;
 112   tp->private = NULL;
 113   thread_list = tp;
 114   return tp;
 115 }
 116
 117 void
 118 delete_thread (pid)
 119      int pid;
 120 {
 121   struct thread_info *tp, *tpprev;
 122
 123   tpprev = NULL;
 124
 125   for (tp = thread_list; tp; tpprev = tp, tp = tp->next)
 126     if (tp->pid == pid)
 127       break;
 128
 129   if (!tp)
 130     return;
 131
 132   if (tpprev)
 133     tpprev->next = tp->next;
 134   else
 135     thread_list = tp->next;
 136
 137   /* NOTE: this will take care of any left-over step_resume breakpoints,
 138      but not any user-specified thread-specific breakpoints. */
 139   if (tp->step_resume_breakpoint)
 140     delete_breakpoint (tp->step_resume_breakpoint);
 141
 142   /* FIXME: do I ever need to call the back-end to give it a
 143      chance at this private data before deleting the thread?  */
 144   if (tp->private)
 145     free (tp->private);
 146
 147   free (tp);
 148
 149   return;
 150 }
 151
 152 static struct thread_info *
 153 find_thread_id (num)
 154      int num;
 155 {
 156   struct thread_info *tp;
 157
 158   for (tp = thread_list; tp; tp = tp->next)
 159     if (tp->num == num)
 160       return tp;
 161
 162   return NULL;
 163 }
 164
 165 /* Find a thread_info by matching 'pid'.  */
 166 struct thread_info *
 167 find_thread_pid (pid)
 168      int pid;
 169 {
 170   struct thread_info *tp;
 171
 172   for (tp = thread_list; tp; tp = tp->next)
 173     if (tp->pid == pid)
 174       return tp;
 175
 176   return NULL;
 177 }
 178
 179 /*
 180  * Thread iterator function.
 181  *
 182  * Calls a callback function once for each thread, so long as
 183  * the callback function returns false.  If the callback function
 184  * returns true, the iteration will end and the current thread
 185  * will be returned.  This can be useful for implementing a
 186  * search for a thread with arbitrary attributes, or for applying
 187  * some operation to every thread.
 188  *
 189  * FIXME: some of the existing functionality, such as
 190  * "Thread apply all", might be rewritten using this functionality.
 191  */
 192
 193 struct thread_info *
 194 iterate_over_threads (callback, data)
 195      int (*callback) ();
 196      void *data;
 197 {
 198   struct thread_info *tp;
 199
 200   for (tp = thread_list; tp; tp = tp->next)
 201     if ((*callback) (tp, data))
 202       return tp;
 203
 204   return NULL;
 205 }
 206
 207 int
 208 valid_thread_id (num)
 209      int num;
 210 {
 211   struct thread_info *tp;
 212
 213   for (tp = thread_list; tp; tp = tp->next)
 214     if (tp->num == num)
 215       return 1;
 216
 217   return 0;
 218 }
 219
 220 int
 221 pid_to_thread_id (pid)
 222      int pid;
 223 {
 224   struct thread_info *tp;
 225
 226   for (tp = thread_list; tp; tp = tp->next)
 227     if (tp->pid == pid)
 228       return tp->num;
 229
 230   return 0;
 231 }
 232
 233 int
 234 thread_id_to_pid (num)
 235      int num;
 236 {
 237   struct thread_info *thread = find_thread_id (num);
 238   if (thread)
 239     return thread->pid;
 240   else
 241     return -1;
 242 }
 243
 244 int
 245 in_thread_list (pid)
 246      int pid;
 247 {
 248   struct thread_info *tp;
 249
 250   for (tp = thread_list; tp; tp = tp->next)
 251     if (tp->pid == pid)
 252       return 1;
 253
 254   return 0;                     /* Never heard of 'im */
 255 }
 256 #ifdef UI_OUT
 257 /* Print a list of thread ids currently known, and the total number of
 258    threads. To be used from within catch_errors. */
 259 static int
 260 do_captured_list_thread_ids (void *arg)
 261 {
 262   struct thread_info *tp;
 263   int num = 0;
 264
 265   ui_out_list_begin (uiout, "thread-ids");
 266
 267   for (tp = thread_list; tp; tp = tp->next)
 268     {
 269       num++;
 270       ui_out_field_int (uiout, "thread-id", tp->num);
 271     }
 272
 273   ui_out_list_end (uiout);
 274   ui_out_field_int (uiout, "number-of-threads", num);
 275   return GDB_RC_OK;
 276 }
 277
 278 /* Official gdblib interface function to get a list of thread ids and
 279    the total number. */
 280 enum gdb_rc
 281 gdb_list_thread_ids (/* output object */)
 282 {
 283   return catch_errors (do_captured_list_thread_ids, NULL,
 284                        NULL, RETURN_MASK_ALL);
 285 }
 286 #endif
 287
 288 /* Load infrun state for the thread PID.  */
 289
 290 void
 291 load_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 292                    trap_expected, step_resume_breakpoint,
 293                    through_sigtramp_breakpoint, step_range_start,
 294                    step_range_end, step_frame_address,
 295                    handling_longjmp, another_trap,
 296                    stepping_through_solib_after_catch,
 297                    stepping_through_solib_catchpoints,
 298                    stepping_through_sigtramp)
 299      int pid;
 300      CORE_ADDR *prev_pc;
 301      CORE_ADDR *prev_func_start;
 302      char **prev_func_name;
 303      int *trap_expected;
 304      struct breakpoint **step_resume_breakpoint;
 305      struct breakpoint **through_sigtramp_breakpoint;
 306      CORE_ADDR *step_range_start;
 307      CORE_ADDR *step_range_end;
 308      CORE_ADDR *step_frame_address;
 309      int *handling_longjmp;
 310      int *another_trap;
 311      int *stepping_through_solib_after_catch;
 312      bpstat *stepping_through_solib_catchpoints;
 313      int *stepping_through_sigtramp;
 314 {
 315   struct thread_info *tp;
 316
 317   /* If we can't find the thread, then we're debugging a single threaded
 318      process.  No need to do anything in that case.  */
 319   tp = find_thread_id (pid_to_thread_id (pid));
 320   if (tp == NULL)
 321     return;
 322
 323   *prev_pc = tp->prev_pc;
 324   *prev_func_start = tp->prev_func_start;
 325   *prev_func_name = tp->prev_func_name;
 326   *step_resume_breakpoint = tp->step_resume_breakpoint;
 327   *step_range_start = tp->step_range_start;
 328   *step_range_end = tp->step_range_end;
 329   *step_frame_address = tp->step_frame_address;
 330   *through_sigtramp_breakpoint = tp->through_sigtramp_breakpoint;
 331   *handling_longjmp = tp->handling_longjmp;
 332   *trap_expected = tp->trap_expected;
 333   *another_trap = tp->another_trap;
 334   *stepping_through_solib_after_catch = tp->stepping_through_solib_after_catch;
 335   *stepping_through_solib_catchpoints = tp->stepping_through_solib_catchpoints;
 336   *stepping_through_sigtramp = tp->stepping_through_sigtramp;
 337 }
 338
 339 /* Save infrun state for the thread PID.  */
 340
 341 void
 342 save_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 343                    trap_expected, step_resume_breakpoint,
 344                    through_sigtramp_breakpoint, step_range_start,
 345                    step_range_end, step_frame_address,
 346                    handling_longjmp, another_trap,
 347                    stepping_through_solib_after_catch,
 348                    stepping_through_solib_catchpoints,
 349                    stepping_through_sigtramp)
 350      int pid;
 351      CORE_ADDR prev_pc;
 352      CORE_ADDR prev_func_start;
 353      char *prev_func_name;
 354      int trap_expected;
 355      struct breakpoint *step_resume_breakpoint;
 356      struct breakpoint *through_sigtramp_breakpoint;
 357      CORE_ADDR step_range_start;
 358      CORE_ADDR step_range_end;
 359      CORE_ADDR step_frame_address;
 360      int handling_longjmp;
 361      int another_trap;
 362      int stepping_through_solib_after_catch;
 363      bpstat stepping_through_solib_catchpoints;
 364      int stepping_through_sigtramp;
 365 {
 366   struct thread_info *tp;
 367
 368   /* If we can't find the thread, then we're debugging a single-threaded
 369      process.  Nothing to do in that case.  */
 370   tp = find_thread_id (pid_to_thread_id (pid));
 371   if (tp == NULL)
 372     return;
 373
 374   tp->prev_pc = prev_pc;
 375   tp->prev_func_start = prev_func_start;
 376   tp->prev_func_name = prev_func_name;
 377   tp->step_resume_breakpoint = step_resume_breakpoint;
 378   tp->step_range_start = step_range_start;
 379   tp->step_range_end = step_range_end;
 380   tp->step_frame_address = step_frame_address;
 381   tp->through_sigtramp_breakpoint = through_sigtramp_breakpoint;
 382   tp->handling_longjmp = handling_longjmp;
 383   tp->trap_expected = trap_expected;
 384   tp->another_trap = another_trap;
 385   tp->stepping_through_solib_after_catch = stepping_through_solib_after_catch;
 386   tp->stepping_through_solib_catchpoints = stepping_through_solib_catchpoints;
 387   tp->stepping_through_sigtramp = stepping_through_sigtramp;
 388 }
 389
 390 /* Return true if TP is an active thread. */
 391 static int
 392 thread_alive (tp)
 393      struct thread_info *tp;
 394 {
 395   if (tp->pid == -1)
 396     return 0;
 397   if (!target_thread_alive (tp->pid))
 398     {
 399       tp->pid = -1;             /* Mark it as dead */
 400       return 0;
 401     }
 402   return 1;
 403 }
 404
 405 static void
 406 prune_threads ()
 407 {
 408   struct thread_info *tp, *next;
 409
 410   for (tp = thread_list; tp; tp = next)
 411     {
 412       next = tp->next;
 413       if (!thread_alive (tp))
 414         delete_thread (tp->pid);
 415     }
 416 }
 417
 418 /* Print information about currently known threads
 419
 420  * Note: this has the drawback that it _really_ switches
 421  *       threads, which frees the frame cache.  A no-side
 422  *       effects info-threads command would be nicer.
 423  */
 424
 425 static void
 426 info_threads_command (arg, from_tty)
 427      char *arg;
 428      int from_tty;
 429 {
 430   struct thread_info *tp;
 431   int current_pid;
 432   struct frame_info *cur_frame;
 433   int saved_frame_level = selected_frame_level;
 434   int counter;
 435   char *extra_info;
 436
 437   /* Avoid coredumps which would happen if we tried to access a NULL
 438      selected_frame.  */
 439   if (!target_has_stack)
 440     error ("No stack.");
 441
 442   prune_threads ();
 443   target_find_new_threads ();
 444   current_pid = inferior_pid;
 445   for (tp = thread_list; tp; tp = tp->next)
 446     {
 447       if (tp->pid == current_pid)
 448         printf_filtered ("* ");
 449       else
 450         printf_filtered ("  ");
 451
 452 #ifdef HPUXHPPA
 453       printf_filtered ("%d %s", tp->num, target_tid_to_str (tp->pid));
 454 #else
 455       printf_filtered ("%d %s", tp->num, target_pid_to_str (tp->pid));
 456 #endif
 457
 458       extra_info = target_extra_thread_info (tp);
 459       if (extra_info)
 460         printf_filtered (" (%s)", extra_info);
 461       puts_filtered ("  ");
 462
 463       switch_to_thread (tp->pid);
 464       if (selected_frame)
 465         print_only_stack_frame (selected_frame, -1, 0);
 466       else
 467         printf_filtered ("[No stack.]\n");
 468     }
 469
 470   switch_to_thread (current_pid);
 471
 472   /* Code below copied from "up_silently_base" in "stack.c".
 473    * It restores the frame set by the user before the "info threads"
 474    * command.  We have finished the info-threads display by switching
 475    * back to the current thread.  That switch has put us at the top
 476    * of the stack (leaf frame).
 477    */
 478   counter = saved_frame_level;
 479   cur_frame = find_relative_frame (selected_frame, &counter);
 480   if (counter != 0)
 481     {
 482       /* Ooops, can't restore, tell user where we are. */
 483       warning ("Couldn't restore frame in current thread, at frame 0");
 484       print_stack_frame (selected_frame, -1, 0);
 485     }
 486   else
 487     {
 488       select_frame (cur_frame, saved_frame_level);
 489     }
 490
 491   /* re-show current frame. */
 492   show_stack_frame (cur_frame);
 493 }
 494
 495 /* Switch from one thread to another. */
 496
 497 static void
 498 switch_to_thread (pid)
 499      int pid;
 500 {
 501   if (pid == inferior_pid)
 502     return;
 503
 504   inferior_pid = pid;
 505   flush_cached_frames ();
 506   registers_changed ();
 507   stop_pc = read_pc ();
 508   select_frame (get_current_frame (), 0);
 509 }
 510
 511 static void
 512 restore_current_thread (pid)
 513      int pid;
 514 {
 515   if (pid != inferior_pid)
 516     {
 517       switch_to_thread (pid);
 518       print_stack_frame (get_current_frame (), 0, -1);
 519     }
 520 }
 521
 522 struct current_thread_cleanup
 523 {
 524   int inferior_pid;
 525 };
 526
 527 static void
 528 do_restore_current_thread_cleanup (void *arg)
 529 {
 530   struct current_thread_cleanup *old = arg;
 531   restore_current_thread (old->inferior_pid);
 532   free (old);
 533 }
 534
 535 static struct cleanup *
 536 make_cleanup_restore_current_thread (int inferior_pid)
 537 {
 538   struct current_thread_cleanup *old
 539     = xmalloc (sizeof (struct current_thread_cleanup));
 540   old->inferior_pid = inferior_pid;
 541   return make_cleanup (do_restore_current_thread_cleanup, old);
 542 }
 543
 544 /* Apply a GDB command to a list of threads.  List syntax is a whitespace
 545    seperated list of numbers, or ranges, or the keyword `all'.  Ranges consist
 546    of two numbers seperated by a hyphen.  Examples:
 547
 548    thread apply 1 2 7 4 backtrace       Apply backtrace cmd to threads 1,2,7,4
 549    thread apply 2-7 9 p foo(1)  Apply p foo(1) cmd to threads 2->7 & 9
 550    thread apply all p x/i $pc   Apply x/i $pc cmd to all threads
 551  */
 552
 553 static void
 554 thread_apply_all_command (cmd, from_tty)
 555      char *cmd;
 556      int from_tty;
 557 {
 558   struct thread_info *tp;
 559   struct cleanup *old_chain;
 560
 561   if (cmd == NULL || *cmd == '\000')
 562     error ("Please specify a command following the thread ID list");
 563
 564   old_chain = make_cleanup_restore_current_thread (inferior_pid);
 565
 566   for (tp = thread_list; tp; tp = tp->next)
 567     if (thread_alive (tp))
 568       {
 569         switch_to_thread (tp->pid);
 570 #ifdef HPUXHPPA
 571         printf_filtered ("\nThread %d (%s):\n",
 572                          tp->num,
 573                          target_tid_to_str (inferior_pid));
 574 #else
 575         printf_filtered ("\nThread %d (%s):\n", tp->num,
 576                          target_pid_to_str (inferior_pid));
 577 #endif
 578         execute_command (cmd, from_tty);
 579       }
 580
 581   do_cleanups (old_chain);
 582 }
 583
 584 static void
 585 thread_apply_command (tidlist, from_tty)
 586      char *tidlist;
 587      int from_tty;
 588 {
 589   char *cmd;
 590   char *p;
 591   struct cleanup *old_chain;
 592
 593   if (tidlist == NULL || *tidlist == '\000')
 594     error ("Please specify a thread ID list");
 595
 596   for (cmd = tidlist; *cmd != '\000' && !isalpha (*cmd); cmd++);
 597
 598   if (*cmd == '\000')
 599     error ("Please specify a command following the thread ID list");
 600
 601   old_chain = make_cleanup_restore_current_thread (inferior_pid);
 602
 603   while (tidlist < cmd)
 604     {
 605       struct thread_info *tp;
 606       int start, end;
 607
 608       start = strtol (tidlist, &p, 10);
 609       if (p == tidlist)
 610         error ("Error parsing %s", tidlist);
 611       tidlist = p;
 612
 613       while (*tidlist == ' ' || *tidlist == '\t')
 614         tidlist++;
 615
 616       if (*tidlist == '-')      /* Got a range of IDs? */
 617         {
 618           tidlist++;            /* Skip the - */
 619           end = strtol (tidlist, &p, 10);
 620           if (p == tidlist)
 621             error ("Error parsing %s", tidlist);
 622           tidlist = p;
 623
 624           while (*tidlist == ' ' || *tidlist == '\t')
 625             tidlist++;
 626         }
 627       else
 628         end = start;
 629
 630       for (; start <= end; start++)
 631         {
 632           tp = find_thread_id (start);
 633
 634           if (!tp)
 635             warning ("Unknown thread %d.", start);
 636           else if (!thread_alive (tp))
 637             warning ("Thread %d has terminated.", start);
 638           else
 639             {
 640               switch_to_thread (tp->pid);
 641 #ifdef HPUXHPPA
 642               printf_filtered ("\nThread %d (%s):\n", tp->num,
 643                                target_tid_to_str (inferior_pid));
 644 #else
 645               printf_filtered ("\nThread %d (%s):\n", tp->num,
 646                                target_pid_to_str (inferior_pid));
 647 #endif
 648               execute_command (cmd, from_tty);
 649             }
 650         }
 651     }
 652
 653   do_cleanups (old_chain);
 654 }
 655
 656 /* Switch to the specified thread.  Will dispatch off to thread_apply_command
 657    if prefix of arg is `apply'.  */
 658
 659 static void
 660 thread_command (tidstr, from_tty)
 661      char *tidstr;
 662      int from_tty;
 663 {
 664   if (!tidstr)
 665     {
 666       /* Don't generate an error, just say which thread is current. */
 667       if (target_has_stack)
 668         printf_filtered ("[Current thread is %d (%s)]\n",
 669                          pid_to_thread_id (inferior_pid),
 670 #if defined(HPUXHPPA)
 671                          target_tid_to_str (inferior_pid)
 672 #else
 673                          target_pid_to_str (inferior_pid)
 674 #endif
 675           );
 676       else
 677         error ("No stack.");
 678       return;
 679     }
 680
 681   gdb_thread_select (tidstr);
 682 }
 683
 684 static int
 685 do_captured_thread_select (void *tidstr)
 686 {
 687   int num;
 688   struct thread_info *tp;
 689
 690   num = atoi ((char *)tidstr);
 691
 692   tp = find_thread_id (num);
 693
 694 #ifdef UI_OUT
 695   if (!tp)
 696     error ("Thread ID %d not known.", num);
 697 #else
 698   if (!tp)
 699     error ("Thread ID %d not known.  Use the \"info threads\" command to\n\
 700 see the IDs of currently known threads.", num);
 701 #endif
 702
 703   if (!thread_alive (tp))
 704     error ("Thread ID %d has terminated.\n", num);
 705
 706   switch_to_thread (tp->pid);
 707
 708 #ifdef UI_OUT
 709   ui_out_text (uiout, "[Switching to thread ");
 710   ui_out_field_int (uiout, "new-thread-id", pid_to_thread_id (inferior_pid));
 711   ui_out_text (uiout, " (");
 712 #if defined(HPUXHPPA)
 713   ui_out_text (uiout, target_tid_to_str (inferior_pid));
 714 #else
 715   ui_out_text (uiout, target_pid_to_str (inferior_pid));
 716 #endif
 717   ui_out_text (uiout, ")]");
 718 #else /* UI_OUT */
 719   printf_filtered ("[Switching to thread %d (%s)]\n",
 720                    pid_to_thread_id (inferior_pid),
 721 #if defined(HPUXHPPA)
 722                    target_tid_to_str (inferior_pid)
 723 #else
 724                    target_pid_to_str (inferior_pid)
 725 #endif
 726     );
 727 #endif /* UI_OUT */
 728
 729   print_stack_frame (selected_frame, selected_frame_level, 1);
 730   return GDB_RC_OK;
 731 }
 732
 733 enum gdb_rc
 734 gdb_thread_select (char *tidstr)
 735 {
 736   return catch_errors (do_captured_thread_select, tidstr,
 737                        NULL, RETURN_MASK_ALL);
 738 }
 739
 740 /* Commands with a prefix of `thread'.  */
 741 struct cmd_list_element *thread_cmd_list = NULL;
 742
 743 void
 744 _initialize_thread ()
 745 {
 746   static struct cmd_list_element *thread_apply_list = NULL;
 747
 748   add_info ("threads", info_threads_command,
 749             "IDs of currently known threads.");
 750
 751   add_prefix_cmd ("thread", class_run, thread_command,
 752                   "Use this command to switch between threads.\n\
 753 The new thread ID must be currently known.", &thread_cmd_list, "thread ", 1,
 754                   &cmdlist);
 755
 756   add_prefix_cmd ("apply", class_run, thread_apply_command,
 757                   "Apply a command to a list of threads.",
 758                   &thread_apply_list, "apply ", 1, &thread_cmd_list);
 759
 760   add_cmd ("all", class_run, thread_apply_all_command,
 761            "Apply a command to all threads.",
 762            &thread_apply_list);
 763
 764   if (!xdb_commands)
 765     add_com_alias ("t", "thread", class_run, 1);
 766 }