1 /* writev supports all Linux kernels >= 2.0.
2 Copyright (C) 1997, 1998 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
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 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
22 #include <sys/param.h>
26 #include <sys/syscall.h>
28 extern ssize_t __syscall_writev
__P ((int, const struct iovec
*, int));
29 static ssize_t __atomic_writev_replacement
__P ((int, const struct iovec
*,
30 int)) internal_function
;
33 /* Not all versions of the kernel support the large number of records. */
35 # define UIO_FASTIOV 8 /* 8 is a safe number. */
39 /* We should deal with kernel which have a smaller UIO_FASTIOV as well
40 as a very big count. */
42 __writev (fd
, vector
, count
)
44 const struct iovec
*vector
;
47 int errno_saved
= errno
;
48 ssize_t bytes_written
;
50 bytes_written
= INLINE_SYSCALL (writev
, 3, fd
, vector
, count
);
52 if (bytes_written
>= 0 || errno
!= EINVAL
|| count
<= UIO_FASTIOV
)
55 /* Restore the old error value as if nothing happened. */
56 __set_errno (errno_saved
);
58 return __atomic_writev_replacement (fd
, vector
, count
);
60 weak_alias (__writev
, writev
)
62 #define __writev static internal_function __atomic_writev_replacement
63 #include <sysdeps/posix/writev.c>