ferror.md

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ferror | Microsoft Docs		11/04/2016	cpp-standard-libraries	reference	ferror	msvcrt.dll msvcr80.dll msvcr90.dll msvcr100.dll msvcr100_clr0400.dll msvcr110.dll msvcr110_clr0400.dll msvcr120.dll msvcr120_clr0400.dll ucrtbase.dll api-ms-win-crt-stdio-l1-1-0.dll	DLLExport	ferror	C++	ferror function streams, testing for errors errors [C++], testing for stream	528a34bc-f2aa-4c3f-b89a-5b148e6864f7	corob-msft	corob	cplusplus

ferror

Tests for an error on a stream.

Syntax

int ferror(
   FILE *stream
);

Parameters

stream
Pointer to FILE structure.

Return Value

If no error has occurred on stream, ferror returns 0. Otherwise, it returns a nonzero value. If stream is NULL, ferror invokes the invalid parameter handler, as described in Parameter Validation. If execution is allowed to continue, this function sets errno to EINVAL and returns 0.

See _doserrno, errno, _sys_errlist, and _sys_nerr for more information on these, and other, error codes.

Remarks

The ferror routine (implemented both as a function and as a macro) tests for a reading or writing error on the file associated with stream. If an error has occurred, the error indicator for the stream remains set until the stream is closed or rewound, or until clearerr is called against it.

Requirements

Function	Required header
ferror	<stdio.h>

For additional compatibility information, see Compatibility.

Example

See the example for feof.

See also

Error Handling
Stream I/O
clearerr
_eof
feof
fopen, _wfopen
perror, _wperror