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/****************************************************************************
* libc/stdio/lib_ferror.c
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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. Neither the name NuttX 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdio.h>
#include <errno.h>
#include <nuttx/fs/fs.h>
#if CONFIG_NFILE_STREAMS > 0
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ferror
*
* Description:
* This function will test if the last operation resulted in an eror. This
* is used to disambiguate EOF and error conditions.
*
* Return Value:
* A non-zero value is returned to indicate the error condition.
*
****************************************************************************/
int ferror(FILE *stream)
{
#if 0
/* If an error is encountered by any of the C-buffered I/O functions, they
* should set the __FS_FLAG_ERROR in the fs_flags field of struct
* file_struct.
*/
return (stream->fs_flags & __FS_FLAG_ERROR) != 0;
#else
/* However, nothing currenlty sets the __FS_FLAG_ERROR flag (that is a job
* for another day). The __FS_FLAG_EOF is set by operations that perform
* read operations. Since ferror() is probably only called to disambiguate
* the meaning of other functions that return EOF, to indicate either EOF or
* an error, just testing for not EOF is probably sufficient for now.
*
* This approach would not work if ferror() is called in other contexts. In
* those cases, ferror() will always report an error.
*/
return (stream->fs_flags & __FS_FLAG_EOF) == 0;
#endif
}
#endif /* CONFIG_NFILE_STREAMS */
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