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/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/*
FUNCTION
<<fwrite>>---write array elements
INDEX
fwrite
ANSI_SYNOPSIS
#include <stdio.h>
size_t fwrite(const void *<[buf]>, size_t <[size]>,
size_t <[count]>, FILE *<[fp]>);
TRAD_SYNOPSIS
#include <stdio.h>
size_t fwrite(<[buf]>, <[size]>, <[count]>, <[fp]>)
char *<[buf]>;
size_t <[size]>;
size_t <[count]>;
FILE *<[fp]>;
DESCRIPTION
<<fwrite>> attempts to copy, starting from the memory location
<[buf]>, <[count]> elements (each of size <[size]>) into the file or
stream identified by <[fp]>. <<fwrite>> may copy fewer elements than
<[count]> if an error intervenes.
<<fwrite>> also advances the file position indicator (if any) for
<[fp]> by the number of @emph{characters} actually written.
RETURNS
If <<fwrite>> succeeds in writing all the elements you specify, the
result is the same as the argument <[count]>. In any event, the
result is the number of complete elements that <<fwrite>> copied to
the file.
PORTABILITY
ANSI C requires <<fwrite>>.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "%W% (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */
#include <stdio.h>
#include <string.h>
#if 0
#include <sys/stdc.h>
#endif
#include "local.h"
#if 1
#include "fvwrite.h"
#endif
/*
* Write `count' objects (each size `size') from memory to the given file.
* Return the number of whole objects written.
*/
size_t
_DEFUN (fwrite, (buf, size, count, fp),
_CONST _PTR buf _AND
size_t size _AND
size_t count _AND
FILE * fp)
{
size_t n;
struct __suio uio;
struct __siov iov;
iov.iov_base = buf;
uio.uio_resid = iov.iov_len = n = count * size;
uio.uio_iov = &iov;
uio.uio_iovcnt = 1;
/*
* The usual case is success (__sfvwrite returns 0);
* skip the divide if this happens, since divides are
* generally slow and since this occurs whenever size==0.
*/
_flockfile(fp);
if (__sfvwrite (fp, &uio) == 0)
{
_funlockfile(fp);
return count;
}
_funlockfile(fp);
return (n - uio.uio_resid) / size;
}
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