rt/clock_getcpuclockid.c

   1 /* Copyright (C) 2000, 2001 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   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
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <time.h>
  20 #include <unistd.h>
  21
  22 int
  23 clock_getcpuclockid (pid_t pid, clockid_t *clock_id)
  24 {
  25   /* We don't allow any process ID but our own.  */
  26   if (pid != 0 && pid != getpid ())
  27     return EPERM;
  28
  29 #ifdef CLOCK_PROCESS_CPUTIME_ID
  30   /* Store the number.  */
  31   *clock_id = CLOCK_PROCESS_CPUTIME_ID;
  32
  33   return 0;
  34 #else
  35   /* We don't have a timer for that.  */
  36   return ENOENT;
  37 #endif
  38 }