4.7 feof, feof_unlocked—test for end of file

Synopsis

#include <stdio.h>
int feof(FILE *fp);

#define _BSD_SOURCE
#include <stdio.h>
int feof_unlocked(FILE *fp);

Description
feof tests whether or not the end of the file identified by fp has been reached.

feof_unlocked is a non-thread-safe version of feof. feof_unlocked may only safely be used within a scope protected by flockfile() (or ftrylockfile()) and funlockfile(). This function may safely be used in a multi-threaded program if and only if they are called while the invoking thread owns the (FILE *) object, as is the case after a successful call to the flockfile() or ftrylockfile() functions. If threads are disabled, then feof_unlocked is equivalent to feof.

Returns
feof returns 0 if the end of file has not yet been reached; if at end of file, the result is nonzero.

Portability
feof is required by ANSI C.

feof_unlocked is a BSD extension also provided by GNU libc.

No supporting OS subroutines are required.