1/* $NetBSD: fcntl.h,v 1.57.2.1 2026/06/16 09:06:50 martin Exp $ */
2
3/*-
4 * Copyright (c) 1983, 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * @(#)fcntl.h 8.3 (Berkeley) 1/21/94
37 */
38
39#ifndef _SYS_FCNTL_H_
40#define _SYS_FCNTL_H_
41
42/*
43 * This file includes the definitions for open and fcntl
44 * described by POSIX for <fcntl.h>; it also includes
45 * related kernel definitions.
46 */
47
48#ifndef _KERNEL
49#include <sys/featuretest.h>
50#include <sys/types.h>
51#if defined(_XOPEN_SOURCE)
52#include <sys/stat.h>
53#endif /* _XOPEN_SOURCE */
54#endif /* !_KERNEL */
55
56/*
57 * File status flags: these are used by open(2), fcntl(2).
58 * They are also used (indirectly) in the kernel file structure f_flags,
59 * which is a superset of the open/fcntl flags. Open flags and f_flags
60 * are inter-convertible using OFLAGS(fflags) and FFLAGS(oflags).
61 * Open/fcntl flags begin with O_; kernel-internal flags begin with F.
62 */
63/* open-only flags */
64#define O_RDONLY 0x00000000 /* open for reading only */
65#define O_WRONLY 0x00000001 /* open for writing only */
66#define O_RDWR 0x00000002 /* open for reading and writing */
67#define O_ACCMODE 0x00000003 /* mask for above modes */
68
69/*
70 * Kernel encoding of open mode; separate read and write bits that are
71 * independently testable: 1 greater than the above.
72 *
73 * XXX
74 * FREAD and FWRITE are excluded from the #ifdef _KERNEL so that TIOCFLUSH,
75 * which was documented to use FREAD/FWRITE, continues to work.
76 */
77#if defined(_NETBSD_SOURCE)
78#define FREAD 0x00000001
79#define FWRITE 0x00000002
80#endif
81#define O_NONBLOCK 0x00000004 /* no delay */
82#define O_APPEND 0x00000008 /* set append mode */
83#if defined(_NETBSD_SOURCE)
84#define O_SHLOCK 0x00000010 /* open with shared file lock */
85#define O_EXLOCK 0x00000020 /* open with exclusive file lock */
86#define O_ASYNC 0x00000040 /* signal pgrp when data ready */
87#endif
88#if (_POSIX_C_SOURCE - 0) >= 199309L || \
89 (defined(_XOPEN_SOURCE) && defined(_XOPEN_SOURCE_EXTENDED)) || \
90 (_XOPEN_SOURCE - 0) >= 500 || defined(_NETBSD_SOURCE)
91#define O_SYNC 0x00000080 /* synchronous writes */
92#endif
93#if (_POSIX_C_SOURCE - 0) >= 200809L || defined(_NETBSD_SOURCE)
94#define O_NOFOLLOW 0x00000100 /* don't follow symlinks on the last */
95 /* path component */
96#endif
97#define O_CREAT 0x00000200 /* create if nonexistent */
98#define O_TRUNC 0x00000400 /* truncate to zero length */
99#define O_EXCL 0x00000800 /* error if already exists */
100
101/* defined by POSIX 1003.1; BSD default, but required to be bitwise distinct */
102#define O_NOCTTY 0x00008000 /* don't assign controlling terminal */
103
104#if (_POSIX_C_SOURCE - 0) >= 199309L || (_XOPEN_SOURCE - 0) >= 500 || \
105 defined(_NETBSD_SOURCE)
106#define O_DSYNC 0x00010000 /* write: I/O data completion */
107#define O_RSYNC 0x00020000 /* read: I/O completion as for write */
108#endif
109
110#if defined(_NETBSD_SOURCE)
111#define O_ALT_IO 0x00040000 /* use alternate i/o semantics */
112#define O_DIRECT 0x00080000 /* direct I/O hint */
113#endif
114
115#define O_DIRECTORY 0x00200000 /* fail if not a directory */
116#define O_CLOEXEC 0x00400000 /* set close on exec */
117#if (_POSIX_C_SOURCE - 0) >= 200809L || (_XOPEN_SOURCE - 0 >= 700) || \
118 defined(_NETBSD_SOURCE)
119#define O_SEARCH 0x00800000 /* skip search permission checks */
120#endif
121#if defined(_NETBSD_SOURCE)
122#define O_NOSIGPIPE 0x01000000 /* don't deliver sigpipe */
123#define O_REGULAR 0x02000000 /* fail if not a regular file */
124#endif
125#if (_POSIX_C_SOURCE - 0) >= 200809L || (_XOPEN_SOURCE - 0 >= 700) || \
126 defined(_NETBSD_SOURCE)
127#define O_EXEC 0x04000000 /* open for executing only */
128#endif
129#if (_POSIX_C_SOURCE - 0) >= 202405L || (_XOPEN_SOURCE - 0 >= 800) || \
130 defined(_NETBSD_SOURCE)
131#define O_CLOFORK 0x08000000 /* set close on fork */
132#endif
133
134#ifdef _KERNEL
135/* convert from open() flags to/from fflags; convert O_RD/WR to FREAD/FWRITE */
136#define FFLAGS(oflags) ((oflags) + 1)
137#define OFLAGS(fflags) ((fflags) - 1)
138
139/* all bits settable during open(2) */
140#define O_MASK (O_ACCMODE|O_NONBLOCK|O_APPEND|O_SHLOCK|O_EXLOCK|\
141 O_ASYNC|O_SYNC|O_CREAT|O_TRUNC|O_EXCL|O_DSYNC|\
142 O_RSYNC|O_NOCTTY|O_ALT_IO|O_NOFOLLOW|O_DIRECT|\
143 O_DIRECTORY|O_CLOEXEC|O_CLOFORK|O_NOSIGPIPE|\
144 O_REGULAR|O_EXEC)
145
146#define FEXEC O_EXEC
147#define FMARK 0x00001000 /* mark during gc() */
148#define FDEFER 0x00002000 /* defer for next gc pass */
149#define FHASLOCK 0x00004000 /* descriptor holds advisory lock */
150#define FSCAN 0x00100000 /* scan during gc passes */
151#define FSILENT 0x40000000 /* suppress kernel error messages */
152#define FKIOCTL 0x80000000 /* kernel originated ioctl */
153/* bits settable by fcntl(F_SETFL, ...) */
154#define FCNTLFLAGS (FAPPEND|FASYNC|FFSYNC|FNONBLOCK|FDSYNC|FRSYNC|FALTIO|\
155 FDIRECT|FNOSIGPIPE)
156/* bits to save after open(2) */
157#define FMASK (FREAD|FWRITE|FCNTLFLAGS|FEXEC)
158#endif /* _KERNEL */
159
160/*
161 * The O_* flags used to have only F* names, which were used in the kernel
162 * and by fcntl. We retain the F* names for the kernel f_flags field
163 * and for backward compatibility for fcntl.
164 */
165#if defined(_NETBSD_SOURCE)
166#define FAPPEND O_APPEND /* kernel/compat */
167#define FASYNC O_ASYNC /* kernel/compat */
168#define O_FSYNC O_SYNC /* compat */
169#define FNDELAY O_NONBLOCK /* compat */
170#define O_NDELAY O_NONBLOCK /* compat */
171#endif
172#if defined(_KERNEL)
173#define FNOSIGPIPE O_NOSIGPIPE /* kernel */
174#define FNONBLOCK O_NONBLOCK /* kernel */
175#define FFSYNC O_SYNC /* kernel */
176#define FDSYNC O_DSYNC /* kernel */
177#define FRSYNC O_RSYNC /* kernel */
178#define FALTIO O_ALT_IO /* kernel */
179#define FDIRECT O_DIRECT /* kernel */
180#endif
181
182/*
183 * Constants used for fcntl(2)
184 */
185
186/* command values */
187#define F_DUPFD 0 /* duplicate file descriptor */
188#define F_GETFD 1 /* get file descriptor flags */
189#define F_SETFD 2 /* set file descriptor flags */
190#define F_GETFL 3 /* get file status flags */
191#define F_SETFL 4 /* set file status flags */
192#if (_POSIX_C_SOURCE - 0) >= 200112L || (_XOPEN_SOURCE - 0) >= 500 || \
193 defined(_NETBSD_SOURCE)
194#define F_GETOWN 5 /* get SIGIO/SIGURG proc/pgrp */
195#define F_SETOWN 6 /* set SIGIO/SIGURG proc/pgrp */
196#endif
197#define F_GETLK 7 /* get record locking information */
198#define F_SETLK 8 /* set record locking information */
199#define F_SETLKW 9 /* F_SETLK; wait if blocked */
200#if defined(_NETBSD_SOURCE)
201#define F_CLOSEM 10 /* close all fds >= to the one given */
202#define F_MAXFD 11 /* return the max open fd */
203#endif
204#if (_POSIX_C_SOURCE - 0) >= 200809L || defined(_NETBSD_SOURCE)
205#define F_DUPFD_CLOEXEC 12 /* close on exec duplicated fd */
206#endif
207#if defined(_NETBSD_SOURCE)
208#define F_GETNOSIGPIPE 13 /* get SIGPIPE disposition */
209#define F_SETNOSIGPIPE 14 /* set SIGPIPE disposition */
210#define F_GETPATH 15 /* get pathname associated with fd */
211#define F_ADD_SEALS 16 /* set seals */
212#define F_GET_SEALS 17 /* get seals */
213#endif
214#if (_POSIX_C_SOURCE - 0) >= 202405L || (_XOPEN_SOURCE - 0 >= 800) || \
215 defined(_NETBSD_SOURCE)
216#define F_DUPFD_CLOFORK 18 /* close on fork duplicated fd */
217#endif
218#if defined(_NETBSD_SOURCE)
219#define F_DUPFD_CLOBOTH 19 /* close on exec/fork duplicated fd */
220#endif
221
222/* file descriptor flags (F_GETFD, F_SETFD) */
223#define FD_CLOEXEC 1 /* close-on-exec flag */
224#define FD_CLOFORK 2 /* close-on-fork flag */
225
226/* record locking flags (F_GETLK, F_SETLK, F_SETLKW) */
227#define F_RDLCK 1 /* shared or read lock */
228#define F_UNLCK 2 /* unlock */
229#define F_WRLCK 3 /* exclusive or write lock */
230#ifdef _KERNEL
231#define F_WAIT 0x010 /* Wait until lock is granted */
232#define F_FLOCK 0x020 /* Use flock(2) semantics for lock */
233#define F_POSIX 0x040 /* Use POSIX semantics for lock */
234#endif
235
236/* types of seals (F_ADD_SEALS, F_GET_SEALS) */
237#if defined(_NETBSD_SOURCE)
238#define F_SEAL_SEAL 0x0001 /* prevent further seals from being set */
239#define F_SEAL_SHRINK 0x0002 /* prevent file from shrinking */
240#define F_SEAL_GROW 0x0004 /* prevent file from growing */
241#define F_SEAL_WRITE 0x0008 /* prevent writes */
242#define F_SEAL_FUTURE_WRITE 0x0010 /* prevent future writes while mapped */
243#endif
244
245/* Constants for fcntl's passed to the underlying fs - like ioctl's. */
246#if defined(_NETBSD_SOURCE)
247#define F_PARAM_MASK 0xfff
248#define F_PARAM_LEN(x) (((x) >> 16) & F_PARAM_MASK)
249#define F_PARAM_MAX 4095
250#define F_FSCTL (int)0x80000000 /* This fcntl goes to the fs */
251#define F_FSVOID (int)0x40000000 /* no parameters */
252#define F_FSOUT (int)0x20000000 /* copy out parameter */
253#define F_FSIN (int)0x10000000 /* copy in parameter */
254#define F_FSINOUT (F_FSIN | F_FSOUT)
255#define F_FSDIRMASK (int)0x70000000 /* mask for IN/OUT/VOID */
256#define F_FSPRIV (int)0x00008000 /* command is fs-specific */
257
258/*
259 * Define command macros for operations which, if implemented, must be
260 * the same for all fs's.
261 */
262#define _FCN(inout, num, len) \
263 (F_FSCTL | inout | ((len & F_PARAM_MASK) << 16) | (num))
264#define _FCNO(c) _FCN(F_FSVOID, (c), 0)
265#define _FCNR(c, t) _FCN(F_FSIN, (c), (int)sizeof(t))
266#define _FCNW(c, t) _FCN(F_FSOUT, (c), (int)sizeof(t))
267#define _FCNRW(c, t) _FCN(F_FSINOUT, (c), (int)sizeof(t))
268
269/*
270 * Define command macros for fs-specific commands.
271 */
272#define _FCN_FSPRIV(inout, fs, num, len) \
273 (F_FSCTL | F_FSPRIV | inout | ((len & F_PARAM_MASK) << 16) | \
274 (fs) << 8 | (num))
275#define _FCNO_FSPRIV(f, c) _FCN_FSPRIV(F_FSVOID, (f), (c), 0)
276#define _FCNR_FSPRIV(f, c, t) _FCN_FSPRIV(F_FSIN, (f), (c), (int)sizeof(t))
277#define _FCNW_FSPRIV(f, c, t) _FCN_FSPRIV(F_FSOUT, (f), (c), (int)sizeof(t))
278#define _FCNRW_FSPRIV(f, c, t) _FCN_FSPRIV(F_FSINOUT, (f), (c), (int)sizeof(t))
279
280#endif /* _NETBSD_SOURCE */
281
282/*
283 * Advisory file segment locking data type -
284 * information passed to system by user
285 */
286struct flock {
287 off_t l_start; /* starting offset */
288 off_t l_len; /* len = 0 means until end of file */
289 pid_t l_pid; /* lock owner */
290 short l_type; /* lock type: read/write, etc. */
291 short l_whence; /* type of l_start */
292};
293
294
295#if defined(_NETBSD_SOURCE)
296/* lock operations for flock(2) */
297#define LOCK_SH 0x01 /* shared file lock */
298#define LOCK_EX 0x02 /* exclusive file lock */
299#define LOCK_NB 0x04 /* don't block when locking */
300#define LOCK_UN 0x08 /* unlock file */
301#endif
302
303/* Always ensure that these are consistent with <stdio.h> and <unistd.h>! */
304#ifndef SEEK_SET
305#define SEEK_SET 0 /* set file offset to offset */
306#endif
307#ifndef SEEK_CUR
308#define SEEK_CUR 1 /* set file offset to current plus offset */
309#endif
310#ifndef SEEK_END
311#define SEEK_END 2 /* set file offset to EOF plus offset */
312#endif
313
314/*
315 * posix_advise advisories.
316 */
317
318#define POSIX_FADV_NORMAL 0 /* default advice / no advice */
319#define POSIX_FADV_RANDOM 1 /* random access */
320#define POSIX_FADV_SEQUENTIAL 2 /* sequential access(lower to higher) */
321#define POSIX_FADV_WILLNEED 3 /* be needed in near future */
322#define POSIX_FADV_DONTNEED 4 /* not be needed in near future */
323#define POSIX_FADV_NOREUSE 5 /* be accessed once */
324
325/*
326 * Constants for X/Open Extended API set 2 (a.k.a. C063)
327 */
328#if (_POSIX_C_SOURCE - 0) >= 200809L || (_XOPEN_SOURCE - 0 >= 700) || \
329 defined(_NETBSD_SOURCE)
330#define AT_FDCWD -100 /* Use cwd for relative link target */
331#define AT_EACCESS 0x100 /* Use euig/egid for access checks */
332#define AT_SYMLINK_NOFOLLOW 0x200 /* Do not follow symlinks */
333#define AT_SYMLINK_FOLLOW 0x400 /* Follow symlinks */
334#define AT_REMOVEDIR 0x800 /* Remove directory only */
335#endif
336
337
338#ifndef _KERNEL
339#include <sys/cdefs.h>
340
341__BEGIN_DECLS
342int open(const char *, int, ...);
343int creat(const char *, mode_t);
344int fcntl(int, int, ...);
345#if defined(_NETBSD_SOURCE)
346int flock(int, int);
347#endif /* _NETBSD_SOURCE */
348int posix_fadvise(int, off_t, off_t, int);
349
350/*
351 * The Open Group Base Specifications, Issue 6; IEEE Std 1003.1-2001 (POSIX)
352 */
353#if (_POSIX_C_SOURCE - 0) >= 200112L || (_XOPEN_SOURCE - 0) >= 600 || \
354 defined(_NETBSD_SOURCE)
355int posix_fallocate(int, off_t, off_t);
356#endif
357
358/*
359 * X/Open Extended API set 2 (a.k.a. C063)
360 */
361#if (_POSIX_C_SOURCE - 0) >= 200809L || (_XOPEN_SOURCE - 0 >= 700) || \
362 defined(_NETBSD_SOURCE)
363int openat(int, const char *, int, ...);
364#endif
365
366__END_DECLS
367#endif /* !_KERNEL */
368
369#endif /* !_SYS_FCNTL_H_ */