newlib-cygwin/newlib/libc/stdio/feof.c

77 lines
2.1 KiB
C

/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* and/or other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/*
FUNCTION
<<feof>>, <<feof_unlocked>>---test for end of file
INDEX
feof
INDEX
feof_unlocked
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.
*/
#include <stdio.h>
#include "local.h"
/* A subroutine version of the macro feof. */
#undef feof
int
feof (FILE * fp)
{
int result;
CHECK_INIT(_REENT, fp);
_newlib_flockfile_start (fp);
result = __sfeof (fp);
_newlib_flockfile_end (fp);
return result;
}