setjmp.c 1.1 KB

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  1. /* Introduction to Non-Local Exits
  2. Copyright (C) 1991-2026 Free Software Foundation, Inc.
  3. This program is free software; you can redistribute it and/or
  4. modify it under the terms of the GNU General Public License
  5. as published by the Free Software Foundation; either version 2
  6. of the License, or (at your option) any later version.
  7. This program is distributed in the hope that it will be useful,
  8. but WITHOUT ANY WARRANTY; without even the implied warranty of
  9. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  10. GNU General Public License for more details.
  11. You should have received a copy of the GNU General Public License
  12. along with this program; if not, see <https://www.gnu.org/licenses/>.
  13. */
  14. #include <setjmp.h>
  15. #include <stdlib.h>
  16. #include <stdio.h>
  17. jmp_buf main_loop;
  18. void
  19. abort_to_main_loop (int status)
  20. {
  21. longjmp (main_loop, status);
  22. }
  23. void
  24. do_command (void)
  25. {
  26. char buffer[128];
  27. if (fgets (buffer, 128, stdin) == NULL)
  28. abort_to_main_loop (-1);
  29. else
  30. exit (EXIT_SUCCESS);
  31. }
  32. int
  33. main (void)
  34. {
  35. while (1)
  36. if (setjmp (main_loop))
  37. puts ("Back at main loop....");
  38. else
  39. do_command ();
  40. }