FERROR(3)

NAME
clearerr, feof, ferror, fileno - check and reset stream status

SYNOPSIS
#include <stdio.h>

void clearerr(FILE *stream);
int feof(FILE *stream);
int ferror(FILE *stream);
int fileno(FILE *stream);

DESCRIPTION
The function clearerr clears the end-of-file and error indicators for the stream pointed to by stream.

The function feof tests the end-of-file indicator for the stream pointed to by stream, returning non-zero if it is set. The end-of-file indicator can only be cleared by the function clearerr.

The function ferror tests the error indicator for the stream pointed to by stream, returning non-zero if it is set. The error indicator can only be reset by the clearerr function.

The function fileno examines the argument stream and returns its integer descriptor.

For non-locking counterparts, see unlocked_stdio(3).

ERRORS
These functions should not fail and do not set the external variable errno. (However, in case fileno detects that its argument is not a valid stream, it must return -1 and set errno to EBADF.)

CONFORMING TO
The functions clearerr, feof, and ferror conform to X3.159-1989 (``ANSI C'').

SEE ALSO
open(2), stdio(3), unlocked_stdio(3)