glibc/io/fcntl.h
1995-02-18 01:27:10 +00:00

87 lines
3.2 KiB
C

/* Copyright (C) 1991, 1992, 1994 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the, 1992 Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
/*
* POSIX Standard: 6.5 File Control Operations <fcntl.h>
*/
#ifndef _FCNTL_H
#define _FCNTL_H 1
#include <features.h>
/* This must be early so <fcntlbits.h> can define types winningly. */
__BEGIN_DECLS
/* Get the definitions of O_*, F_*, FD_*: all the
numbers and flag bits for `open', `fcntl', et al. */
#include <fcntlbits.h>
#ifdef __USE_MISC
#ifndef R_OK /* Verbatim from <unistd.h>. Ugh. */
/* Values for the second argument to access.
These may be OR'd together. */
#define R_OK 4 /* Test for read permission. */
#define W_OK 2 /* Test for write permission. */
#define X_OK 1 /* Test for execute permission. */
#define F_OK 0 /* Test for existence. */
#endif
#endif /* Use misc. */
/* Do the file control operation described by CMD on FD.
The remaining arguments are interpreted depending on CMD. */
extern int __fcntl __P ((int __fd, int __cmd, ...));
extern int fcntl __P ((int __fd, int __cmd, ...));
/* Open FILE and return a new file descriptor for it, or -1 on error.
OFLAG determines the type of access used. If O_CREAT is on OFLAG,
the third argument is taken as a `mode_t', the mode of the created file. */
extern int __open __P ((__const char *__file, int __oflag,...));
extern int open __P ((__const char *__file, int __oflag,...));
/* Create and open FILE, with mode MODE.
This takes an `int' MODE argument because that is
what `mode_t' will be widened to. */
extern int creat __P ((__const char *__file, __mode_t __mode));
#ifdef __OPTIMIZE__
#define creat(file, m) __open((file), O_WRONLY|O_CREAT|O_TRUNC, (m))
#endif /* Optimizing. */
#if defined (__USE_MISC) && !defined (F_LOCK)
/* NOTE: These declarations also appear in <unistd.h>; be sure to keep both
files consistent. Some systems have them there and some here, and some
software depends on the macros being defined without including both. */
/* `lockf' is a simpler interface to the locking facilities of `fcntl'.
LEN is always relative to the current file position.
The CMD argument is one of the following. */
#define F_ULOCK 0 /* Unlock a previously locked region. */
#define F_LOCK 1 /* Lock a region for exclusive use. */
#define F_TLOCK 2 /* Test and lock a region for exclusive use. */
#define F_TEST 3 /* Test a region for other processes locks. */
extern int lockf __P ((int __fd, int __cmd, __off_t __len));
#endif
__END_DECLS
#endif /* fcntl.h */