sysdeps/posix/usleep.c

   1 /* Implementation of the BSD usleep function using nanosleep.
   2    Copyright (C) 1996-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <time.h>
  20 #include <unistd.h>
  21
  22 int
  23 usleep (useconds_t useconds)
  24 {
  25   struct timespec ts = { .tv_sec = (long int) (useconds / 1000000),
  26                          .tv_nsec = (long int) (useconds % 1000000) * 1000ul };
  27
  28   /* Note the usleep() is a cancellation point.  But since we call
  29      nanosleep() which itself is a cancellation point we do not have
  30      to do anything here.  */
  31   return __nanosleep (&ts, NULL);
  32 }