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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,
* and/or 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>>, <<fwrite_unlocked>>---write array elements
INDEX
fwrite
INDEX
fwrite_unlocked
INDEX
_fwrite_r
INDEX
_fwrite_unlocked_r
SYNOPSIS
#include <stdio.h>
size_t fwrite(const void *restrict <[buf]>, size_t <[size]>,
size_t <[count]>, FILE *restrict <[fp]>);
#define _BSD_SOURCE
#include <stdio.h>
size_t fwrite_unlocked(const void *restrict <[buf]>, size_t <[size]>,
size_t <[count]>, FILE *restrict <[fp]>);
#include <stdio.h>
size_t fwrite( const void *restrict <[buf]>, size_t <[size]>,
size_t <[count]>, FILE *restrict <[fp]>);
#include <stdio.h>
size_t fwrite_unlocked( const void *restrict <[buf]>, size_t <[size]>,
size_t <[count]>, FILE *restrict <[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.
<<fwrite_unlocked>> is a non-thread-safe version of <<fwrite>>.
<<fwrite_unlocked>> may only safely be used within a scope
protected by flockfile() (or ftrylockfile()) and funlockfile(). This
function may safely be used in a multi-threaded program if and only
if they are called while the invoking thread owns the (FILE *)
object, as is the case after a successful call to the flockfile() or
ftrylockfile() functions. If threads are disabled, then
<<fwrite_unlocked>> is equivalent to <<fwrite>>.
<<_fwrite_r>> and <<_fwrite_unlocked_r>> are simply reentrant versions of the
above that take an additional reentrant structure argument: <[ptr]>.
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>>.
<<fwrite_unlocked>> is a BSD extension also provided by GNU libc.
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 */
#define _DEFAULT_SOURCE
#include <_ansi.h>
#include <stdio.h>
#include <string.h>
#if 0
#include <sys/stdc.h>
#endif
#include "local.h"
#if 1
#include "fvwrite.h"
#endif
#ifdef __IMPL_UNLOCKED__
#define _fwrite_r _fwrite_unlocked_r
#define fwrite fwrite_unlocked
#endif
/*
* Write `count' objects (each size `size') from memory to the given file.
* Return the number of whole objects written.
*/
size_t
fwrite (
const void *__restrict buf,
size_t size,
size_t count,
FILE * __restrict fp)
{
size_t n;
#ifdef _FVWRITE_IN_STREAMIO
struct __suio uio;
struct __siov iov;
iov.iov_base = buf;
if (!(uio.uio_resid = iov.iov_len = n = count * size))
return 0;
uio.uio_iov = &iov;
uio.uio_iovcnt = 1;
/*
* The usual case is success (__sfvwrite_r returns 0);
* skip the divide if this happens, since divides are
* generally slow and since this occurs whenever size==0.
*/
CHECK_INIT(ptr, fp);
_newlib_flockfile_start (fp);
ORIENT (fp, -1);
if (_sfvwrite ( fp, &uio) == 0)
{
_newlib_flockfile_exit (fp);
return count;
}
_newlib_flockfile_end (fp);
return (n - uio.uio_resid) / size;
#else
size_t i = 0;
const char *p = buf;
if (!(n = count * size))
return 0;
CHECK_INIT (ptr, fp);
_newlib_flockfile_start (fp);
ORIENT (fp, -1);
/* Make sure we can write. */
if (cantwrite (ptr, fp))
goto ret;
while (i < n)
{
if (_sputc ( p[i], fp) == EOF)
break;
i++;
}
ret:
_newlib_flockfile_end (fp);
return i / size;
#endif
}
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