sysdeps/unix/sysv/linux/eventfd.c

   1 /* Copyright (C) 2007, 2008 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, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <errno.h>
  20 #include <sys/eventfd.h>
  21 #include <sysdep.h>
  22
  23
  24 int
  25 eventfd (int count, int flags)
  26 {
  27 #ifdef __NR_eventfd2
  28   return INLINE_SYSCALL (eventfd2, 2, count, flags);
  29 #else
  30   /* The old system call has no flag parameter which is bad.  So we have
  31      to wait until we have to support to pass additional values to the
  32      kernel (sys_indirect) before implementing setting flags like
  33      O_NONBLOCK etc.  */
  34   if (flags != 0)
  35     {
  36       __set_errno (EINVAL);
  37       return -1;
  38     }
  39
  40 # ifdef __NR_eventfd
  41   return INLINE_SYSCALL (eventfd, 1, count);
  42 # else
  43   __set_errno (ENOSYS);
  44   return -1;
  45 # endif
  46 #endif
  47 }