clearerr-s.md

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Learn more about: clearerr_s	clearerr_s	4/2/2020	clearerr_s _o_clearerr_s	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	apiref	clearerr_s	error indicator for streams resetting stream error indicator clearerr_s function	b74d014d-b7a8-494a-a330-e5ffd5614772

clearerr_s

Resets the error indicator for a stream. This function is a version of clearerr with security enhancements as described in Security features in the CRT.

Syntax

errno_t clearerr_s(
   FILE *stream
);

Parameters

stream
Pointer to FILE structure

Return value

Zero if successful; EINVAL if stream is NULL.

Remarks

The clearerr_s function resets the error indicator and end-of-file indicator for stream. Error indicators aren't automatically cleared; once the error indicator for a specified stream is set, operations on that stream continue to return an error value until clearerr_s, clearerr, fseek, fsetpos, or rewind is called.

If stream is NULL, the invalid parameter handler is invoked, as described in Parameter validation. If execution is allowed to continue, this function sets errno to EINVAL and returns EINVAL.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

Routine	Required header
clearerr_s	<stdio.h>

For more compatibility information, see Compatibility.

Example

// crt_clearerr_s.c
// This program creates an error
// on the standard input stream, then clears
// it so that future reads won't fail.

#include <stdio.h>

int main( void )
{
   int c;
   errno_t err;

   // Create an error by writing to standard input.
   putc( 'c', stdin );
   if( ferror( stdin ) )
   {
      perror( "Write error" );
      err = clearerr_s( stdin );
      if (err != 0)
      {
         abort();
      }
   }

   // See if read causes an error.
   printf( "Will input cause an error? " );
   c = getc( stdin );
   if( ferror( stdin ) )
   {
      perror( "Read error" );
      err = clearerr_s( stdin );
      if (err != 0)
      {
         abort();
      }
   }
}

Input

n

Output

Write error: Bad file descriptor
Will input cause an error? n

See also

Error handling
Stream I/O
clearerr
_eof
feof
ferror
perror, _wperror