glibc/streams/isastream.c

35 lines
1.1 KiB
C

/* Copyright (C) 1998-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <fcntl.h>
#include <stropts.h>
int
isastream (fildes)
int fildes;
{
/* In general we do not have a STREAMS implementation and therefore
return 0. But for invalid file descriptors we have to return an
error. */
if (__fcntl (fildes, F_GETFD) < 0)
return -1;
/* No STREAM. */
return 0;
}