1/* $OpenBSD: fcntl.h,v 1.23 2025/08/04 04:59:30 guenther Exp $ */
2/* $NetBSD: fcntl.h,v 1.8 1995/03/26 20:24:12 jtc Exp $ */
3
4/*-
5 * Copyright (c) 1983, 1990, 1993
6 * The Regents of the University of California. All rights reserved.
7 * (c) UNIX System Laboratories, Inc.
8 * All or some portions of this file are derived from material licensed
9 * to the University of California by American Telephone and Telegraph
10 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
11 * the permission of UNIX System Laboratories, Inc.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)fcntl.h 8.3 (Berkeley) 1/21/94
38 */
39
40#ifndef _SYS_FCNTL_H_
41#define _SYS_FCNTL_H_
42
43/*
44 * This file includes the definitions for open and fcntl
45 * described by POSIX for <fcntl.h>; it also includes
46 * related kernel definitions.
47 */
48
49#include <sys/cdefs.h>
50#ifndef _KERNEL
51#include <sys/types.h>
52#endif
53
54/*
55 * File status flags: these are used by open(2), fcntl(2).
56 * They are also used (indirectly) in the kernel file structure f_flags,
57 * which is a superset of the open/fcntl flags. Open flags and f_flags
58 * are inter-convertible using OFLAGS(fflags) and FFLAGS(oflags).
59 * Open/fcntl flags begin with O_; kernel-internal flags begin with F.
60 */
61/* open-only flags */
62#define O_RDONLY 0x0000 /* open for reading only */
63#define O_WRONLY 0x0001 /* open for writing only */
64#define O_RDWR 0x0002 /* open for reading and writing */
65#define O_ACCMODE 0x0003 /* mask for above modes */
66
67/*
68 * Kernel encoding of open mode; separate read and write bits that are
69 * independently testable: 1 greater than the above.
70 *
71 * XXX
72 * FREAD and FWRITE are excluded from the #ifdef _KERNEL so that TIOCFLUSH,
73 * which was documented to use FREAD/FWRITE, continues to work.
74 */
75#if __BSD_VISIBLE
76#define FREAD 0x0001
77#define FWRITE 0x0002
78#endif
79#define O_NONBLOCK 0x0004 /* no delay */
80#define O_APPEND 0x0008 /* set append mode */
81#if __BSD_VISIBLE
82#define O_SHLOCK 0x0010 /* open with shared file lock */
83#define O_EXLOCK 0x0020 /* open with exclusive file lock */
84#define O_ASYNC 0x0040 /* signal pgrp when data ready */
85#define O_FSYNC 0x0080 /* backwards compatibility */
86#endif
87#if __POSIX_VISIBLE >= 199309 || __XPG_VISIBLE >= 420
88#define O_SYNC 0x0080 /* synchronous writes */
89/*
90 * POSIX 1003.1 permits a higher granularity for synchronous operations
91 * than we support. Since synchronicity is all or nothing in OpenBSD
92 * we just define these to be the same as O_SYNC.
93 */
94#define O_DSYNC O_SYNC /* synchronous data writes */
95#define O_RSYNC O_SYNC /* synchronous reads */
96#endif
97
98/* defined by POSIX Issue 7 */
99#define O_NOFOLLOW 0x0100 /* if path is a symlink, don't follow */
100
101#define O_CREAT 0x0200 /* create if nonexistent */
102#define O_TRUNC 0x0400 /* truncate to zero length */
103#define O_EXCL 0x0800 /* error if already exists */
104
105/* defined by POSIX 1003.1; BSD default, this bit is not required */
106#define O_NOCTTY 0x8000 /* don't assign controlling terminal */
107
108/* defined by POSIX Issue 7 */
109#define O_CLOEXEC 0x10000 /* atomically set FD_CLOEXEC */
110#define O_DIRECTORY 0x20000 /* fail if not a directory */
111
112/* defined by POSIX Issue 8 */
113#define O_CLOFORK 0x40000 /* atomically set FD_CLOFORK */
114
115#ifdef _KERNEL
116/*
117 * convert from open() flags to/from fflags; convert O_RD/WR to FREAD/FWRITE.
118 * For out-of-range values for the flags, be slightly careful (but lossy).
119 */
120#define FFLAGS(oflags) (((oflags) & ~O_ACCMODE) | (((oflags) + 1) & O_ACCMODE))
121#define OFLAGS(fflags) (((fflags) & ~O_ACCMODE) | (((fflags) - 1) & O_ACCMODE))
122
123/* bits to save after open */
124#define FMASK (FREAD|FWRITE|FAPPEND|FASYNC|FFSYNC|FNONBLOCK)
125/* bits settable by fcntl(F_SETFL, ...) */
126#define FCNTLFLAGS (FAPPEND|FASYNC|FFSYNC|FNONBLOCK)
127#endif
128
129/*
130 * The O_* flags used to have only F* names, which were used in the kernel
131 * and by fcntl. We retain the F* names for the kernel f_flags field
132 * and for backward compatibility for fcntl.
133 */
134#if __BSD_VISIBLE
135#define FAPPEND O_APPEND /* kernel/compat */
136#define FASYNC O_ASYNC /* kernel/compat */
137#define FFSYNC O_SYNC /* kernel */
138#define FNONBLOCK O_NONBLOCK /* kernel */
139#define FNDELAY O_NONBLOCK /* compat */
140#define O_NDELAY O_NONBLOCK /* compat */
141#endif
142
143/*
144 * Constants used for fcntl(2)
145 */
146
147/* command values */
148#define F_DUPFD 0 /* duplicate file descriptor */
149#define F_GETFD 1 /* get file descriptor flags */
150#define F_SETFD 2 /* set file descriptor flags */
151#define F_GETFL 3 /* get file status flags */
152#define F_SETFL 4 /* set file status flags */
153#if __POSIX_VISIBLE >= 200112 || __XPG_VISIBLE >= 500
154#define F_GETOWN 5 /* get SIGIO/SIGURG proc/pgrp */
155#define F_SETOWN 6 /* set SIGIO/SIGURG proc/pgrp */
156#endif
157#define F_GETLK 7 /* get record locking information */
158#define F_SETLK 8 /* set record locking information */
159#define F_SETLKW 9 /* F_SETLK; wait if blocked */
160#if __POSIX_VISIBLE >= 200809
161#define F_DUPFD_CLOEXEC 10 /* duplicate with FD_CLOEXEC set */
162#endif
163#if __BSD_VISIBLE
164#define F_ISATTY 11 /* used by isatty(3) */
165#endif
166#if __POSIX_VISIBLE >= 202405
167#define F_DUPFD_CLOFORK 12 /* duplicate with FD_CLOFORK set */
168#endif
169
170/* file descriptor flags (F_GETFD, F_SETFD) */
171#define FD_CLOEXEC 1 /* close-on-exec flag */
172#if __POSIX_VISIBLE >= 202405
173#define FD_CLOFORK 4 /* close-on-fork flag */
174#endif
175
176/* record locking flags (F_GETLK, F_SETLK, F_SETLKW) */
177#define F_RDLCK 1 /* shared or read lock */
178#define F_UNLCK 2 /* unlock */
179#define F_WRLCK 3 /* exclusive or write lock */
180#ifdef _KERNEL
181#define F_WAIT 0x010 /* Wait until lock is granted */
182#define F_FLOCK 0x020 /* Use flock(2) semantics for lock */
183#define F_POSIX 0x040 /* Use POSIX semantics for lock */
184#define F_INTR 0x080 /* Lock operation interrupted */
185#endif
186
187/*
188 * Advisory file segment locking data type -
189 * information passed to system by user
190 */
191struct flock {
192 off_t l_start; /* starting offset */
193 off_t l_len; /* len = 0 means until end of file */
194 pid_t l_pid; /* lock owner */
195 short l_type; /* lock type: read/write, etc. */
196 short l_whence; /* type of l_start */
197};
198
199
200#if __BSD_VISIBLE
201/* lock operations for flock(2) */
202#define LOCK_SH 0x01 /* shared file lock */
203#define LOCK_EX 0x02 /* exclusive file lock */
204#define LOCK_NB 0x04 /* don't block when locking */
205#define LOCK_UN 0x08 /* unlock file */
206#endif
207
208#if __POSIX_VISIBLE >= 200809
209#define AT_FDCWD -100
210
211#define AT_EACCESS 0x01
212#define AT_SYMLINK_NOFOLLOW 0x02
213#define AT_SYMLINK_FOLLOW 0x04
214#define AT_REMOVEDIR 0x08
215#endif
216
217#ifndef _KERNEL
218__BEGIN_DECLS
219int open(const char *, int, ...);
220int creat(const char *, mode_t);
221int fcntl(int, int, ...);
222#if __BSD_VISIBLE
223int flock(int, int);
224#endif
225#if __POSIX_VISIBLE >= 200809
226int openat(int, const char *, int, ...);
227#endif
228__END_DECLS
229#endif
230
231#endif /* !_SYS_FCNTL_H_ */