coreutils/lib/full-write.c
2000-05-01 14:40:08 +00:00

67 lines
1.8 KiB
C

/* full-write.c -- an interface to write that retries after interrupts
Copyright (C) 1993, 1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Copied largely from GNU C's cccp.c.
*/
#if HAVE_CONFIG_H
# include <config.h>
#endif
#include <sys/types.h>
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#include <errno.h>
#ifndef errno
extern int errno;
#endif
/* Write LEN bytes at PTR to descriptor DESC, retrying if interrupted.
Return LEN upon success, write's (negative) error code otherwise. */
int
full_write (int desc, const char *ptr, size_t len)
{
int total_written;
total_written = 0;
while (len > 0)
{
int written = write (desc, ptr, len);
/* write on an old Slackware Linux 1.2.13 returns zero when
I try to write more data than there is room on a floppy disk.
This puts dd into an infinite loop. Reproduce with
dd if=/dev/zero of=/dev/fd0. If you have this problem,
consider upgrading to a newer kernel. */
if (written < 0)
{
#ifdef EINTR
if (errno == EINTR)
continue;
#endif
return written;
}
total_written += written;
ptr += written;
len -= written;
}
return total_written;
}