Files
vxWorks/libc/stdio/fwrite.c
2025-08-20 18:25:46 +08:00

110 lines
3.7 KiB
C

/* fwrite.c - write to a file. stdio.h */
/* Copyright 1992-1993 Wind River Systems, Inc. */
/*
modification history
--------------------
01c,05mar93,jdi documentation cleanup for 5.1.
01b,20sep92,smb documentation additions
01a,29jul92,jcf Added OBJ_VERIFY
+smb taken from UCB stdio
*/
/*
DESCRIPTION
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Chris Torek.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
INCLUDE FILE: stdio.h
SEE ALSO: American National Standard X3.159-1989
NOMANUAL
*/
#include "vxWorks.h"
#include "objLib.h"
#include "private/stdioP.h"
#include "private/fvwriteP.h"
/******************************************************************************
*
* fwrite - write from a specified array (ANSI)
*
* This routine writes, from the array <buf>, up to <count> elements whose
* size is <size>, to a specified stream. The file position indicator for
* the stream (if defined) is advanced by the number of characters
* successfully written. If an error occurs, the resulting value of the file
* position indicator for the stream is indeterminate.
*
* INCLUDE FILES: stdio.h
*
* RETURNS:
* The number of elements successfully written, which will be less than
* <count> only if a write error is encountered.
*/
int fwrite
(
const void * buf, /* where to copy from */
size_t size, /* element size */
size_t count, /* no. of elements */
FILE * fp /* stream to write to */
)
{
size_t n;
struct __suio uio;
struct __siov iov;
if (OBJ_VERIFY (fp, fpClassId) != OK)
return (0);
iov.iov_base = (void *)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.
*/
if (__sfvwrite(fp, &uio) == 0)
return (count);
return ((n - uio.uio_resid) / size);
}