busybox/libbb/full_write.c

43 lines
815 B
C
Raw Normal View History

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
/*
* Write all of the supplied buffer out to a file.
* This does multiple writes as necessary.
* Returns the amount written, or -1 on an error.
*/
ssize_t full_write(int fd, const void *buf, size_t len)
{
2003-03-19 14:43:01 +05:30
ssize_t cc;
ssize_t total;
total = 0;
while (len) {
cc = safe_write(fd, buf, len);
if (cc < 0) {
if (total) {
/* we already wrote some! */
/* user can do another write to know the error code */
return total;
}
return cc; /* write() returns -1 on failure. */
}
total += cc;
2003-03-19 14:43:01 +05:30
buf = ((const char *)buf) + cc;
len -= cc;
}
return total;
}