clock_getcpuclockid.c 1.6 KB

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  1. /* Get a clockid_t for the process CPU clock of a given process. Generic.
  2. Copyright (C) 2000-2026 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library 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 GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <https://www.gnu.org/licenses/>. */
  15. #include <errno.h>
  16. #include <time.h>
  17. #include <unistd.h>
  18. #include <shlib-compat.h>
  19. int
  20. __clock_getcpuclockid (pid_t pid, clockid_t *clock_id)
  21. {
  22. /* We don't allow any process ID but our own. */
  23. if (pid != 0 && pid != getpid ())
  24. return EPERM;
  25. #ifdef CLOCK_PROCESS_CPUTIME_ID
  26. /* Store the number. */
  27. *clock_id = CLOCK_PROCESS_CPUTIME_ID;
  28. return 0;
  29. #else
  30. /* We don't have a timer for that. */
  31. return ENOENT;
  32. #endif
  33. }
  34. versioned_symbol (libc, __clock_getcpuclockid, clock_getcpuclockid, GLIBC_2_17);
  35. /* clock_getcpuclockid moved to libc in version 2.17;
  36. old binaries may expect the symbol version it had in librt. */
  37. #if SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_17)
  38. compat_symbol (libc, __clock_getcpuclockid, clock_getcpuclockid, GLIBC_2_2);
  39. #endif