1/* Copyright (C) 1991-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18/*
19 * POSIX Standard: 2.10 Symbolic Constants <unistd.h>
20 */
21
22#ifndef _UNISTD_H
23#define _UNISTD_H 1
24
25#include <features.h>
26
27__BEGIN_DECLS
28
29/* These may be used to determine what facilities are present at compile time.
30 Their values can be obtained at run time from `sysconf'. */
31
32#ifdef __USE_XOPEN2K8
33/* POSIX Standard approved as ISO/IEC 9945-1 as of September 2008. */
34# define _POSIX_VERSION 200809L
35#elif defined __USE_XOPEN2K
36/* POSIX Standard approved as ISO/IEC 9945-1 as of December 2001. */
37# define _POSIX_VERSION 200112L
38#elif defined __USE_POSIX199506
39/* POSIX Standard approved as ISO/IEC 9945-1 as of June 1995. */
40# define _POSIX_VERSION 199506L
41#elif defined __USE_POSIX199309
42/* POSIX Standard approved as ISO/IEC 9945-1 as of September 1993. */
43# define _POSIX_VERSION 199309L
44#else
45/* POSIX Standard approved as ISO/IEC 9945-1 as of September 1990. */
46# define _POSIX_VERSION 199009L
47#endif
48
49/* These are not #ifdef __USE_POSIX2 because they are
50 in the theoretically application-owned namespace. */
51
52#ifdef __USE_XOPEN2K8
53# define __POSIX2_THIS_VERSION 200809L
54/* The utilities on GNU systems also correspond to this version. */
55#elif defined __USE_XOPEN2K
56/* The utilities on GNU systems also correspond to this version. */
57# define __POSIX2_THIS_VERSION 200112L
58#elif defined __USE_POSIX199506
59/* The utilities on GNU systems also correspond to this version. */
60# define __POSIX2_THIS_VERSION 199506L
61#else
62/* The utilities on GNU systems also correspond to this version. */
63# define __POSIX2_THIS_VERSION 199209L
64#endif
65
66/* The utilities on GNU systems also correspond to this version. */
67#define _POSIX2_VERSION __POSIX2_THIS_VERSION
68
69/* This symbol was required until the 2001 edition of POSIX. */
70#define _POSIX2_C_VERSION __POSIX2_THIS_VERSION
71
72/* If defined, the implementation supports the
73 C Language Bindings Option. */
74#define _POSIX2_C_BIND __POSIX2_THIS_VERSION
75
76/* If defined, the implementation supports the
77 C Language Development Utilities Option. */
78#define _POSIX2_C_DEV __POSIX2_THIS_VERSION
79
80/* If defined, the implementation supports the
81 Software Development Utilities Option. */
82#define _POSIX2_SW_DEV __POSIX2_THIS_VERSION
83
84/* If defined, the implementation supports the
85 creation of locales with the localedef utility. */
86#define _POSIX2_LOCALEDEF __POSIX2_THIS_VERSION
87
88/* X/Open version number to which the library conforms. It is selectable. */
89#ifdef __USE_XOPEN2K8
90# define _XOPEN_VERSION 700
91#elif defined __USE_XOPEN2K
92# define _XOPEN_VERSION 600
93#elif defined __USE_UNIX98
94# define _XOPEN_VERSION 500
95#else
96# define _XOPEN_VERSION 4
97#endif
98
99/* Commands and utilities from XPG4 are available. */
100#define _XOPEN_XCU_VERSION 4
101
102/* We are compatible with the old published standards as well. */
103#define _XOPEN_XPG2 1
104#define _XOPEN_XPG3 1
105#define _XOPEN_XPG4 1
106
107/* The X/Open Unix extensions are available. */
108#define _XOPEN_UNIX 1
109
110/* The enhanced internationalization capabilities according to XPG4.2
111 are present. */
112#define _XOPEN_ENH_I18N 1
113
114/* The legacy interfaces are also available. */
115#define _XOPEN_LEGACY 1
116
117
118/* Get values of POSIX options:
119
120 If these symbols are defined, the corresponding features are
121 always available. If not, they may be available sometimes.
122 The current values can be obtained with `sysconf'.
123
124 _POSIX_JOB_CONTROL Job control is supported.
125 _POSIX_SAVED_IDS Processes have a saved set-user-ID
126 and a saved set-group-ID.
127 _POSIX_REALTIME_SIGNALS Real-time, queued signals are supported.
128 _POSIX_PRIORITY_SCHEDULING Priority scheduling is supported.
129 _POSIX_TIMERS POSIX.4 clocks and timers are supported.
130 _POSIX_ASYNCHRONOUS_IO Asynchronous I/O is supported.
131 _POSIX_PRIORITIZED_IO Prioritized asynchronous I/O is supported.
132 _POSIX_SYNCHRONIZED_IO Synchronizing file data is supported.
133 _POSIX_FSYNC The fsync function is present.
134 _POSIX_MAPPED_FILES Mapping of files to memory is supported.
135 _POSIX_MEMLOCK Locking of all memory is supported.
136 _POSIX_MEMLOCK_RANGE Locking of ranges of memory is supported.
137 _POSIX_MEMORY_PROTECTION Setting of memory protections is supported.
138 _POSIX_MESSAGE_PASSING POSIX.4 message queues are supported.
139 _POSIX_SEMAPHORES POSIX.4 counting semaphores are supported.
140 _POSIX_SHARED_MEMORY_OBJECTS POSIX.4 shared memory objects are supported.
141 _POSIX_THREADS POSIX.1c pthreads are supported.
142 _POSIX_THREAD_ATTR_STACKADDR Thread stack address attribute option supported.
143 _POSIX_THREAD_ATTR_STACKSIZE Thread stack size attribute option supported.
144 _POSIX_THREAD_SAFE_FUNCTIONS Thread-safe functions are supported.
145 _POSIX_THREAD_PRIORITY_SCHEDULING
146 POSIX.1c thread execution scheduling supported.
147 _POSIX_THREAD_PRIO_INHERIT Thread priority inheritance option supported.
148 _POSIX_THREAD_PRIO_PROTECT Thread priority protection option supported.
149 _POSIX_THREAD_PROCESS_SHARED Process-shared synchronization supported.
150 _POSIX_PII Protocol-independent interfaces are supported.
151 _POSIX_PII_XTI XTI protocol-indep. interfaces are supported.
152 _POSIX_PII_SOCKET Socket protocol-indep. interfaces are supported.
153 _POSIX_PII_INTERNET Internet family of protocols supported.
154 _POSIX_PII_INTERNET_STREAM Connection-mode Internet protocol supported.
155 _POSIX_PII_INTERNET_DGRAM Connectionless Internet protocol supported.
156 _POSIX_PII_OSI ISO/OSI family of protocols supported.
157 _POSIX_PII_OSI_COTS Connection-mode ISO/OSI service supported.
158 _POSIX_PII_OSI_CLTS Connectionless ISO/OSI service supported.
159 _POSIX_POLL Implementation supports `poll' function.
160 _POSIX_SELECT Implementation supports `select' and `pselect'.
161
162 _XOPEN_REALTIME X/Open realtime support is available.
163 _XOPEN_REALTIME_THREADS X/Open realtime thread support is available.
164 _XOPEN_SHM Shared memory interface according to XPG4.2.
165
166 _XBS5_ILP32_OFF32 Implementation provides environment with 32-bit
167 int, long, pointer, and off_t types.
168 _XBS5_ILP32_OFFBIG Implementation provides environment with 32-bit
169 int, long, and pointer and off_t with at least
170 64 bits.
171 _XBS5_LP64_OFF64 Implementation provides environment with 32-bit
172 int, and 64-bit long, pointer, and off_t types.
173 _XBS5_LPBIG_OFFBIG Implementation provides environment with at
174 least 32 bits int and long, pointer, and off_t
175 with at least 64 bits.
176
177 If any of these symbols is defined as -1, the corresponding option is not
178 true for any file. If any is defined as other than -1, the corresponding
179 option is true for all files. If a symbol is not defined at all, the value
180 for a specific file can be obtained from `pathconf' and `fpathconf'.
181
182 _POSIX_CHOWN_RESTRICTED Only the super user can use `chown' to change
183 the owner of a file. `chown' can only be used
184 to change the group ID of a file to a group of
185 which the calling process is a member.
186 _POSIX_NO_TRUNC Pathname components longer than
187 NAME_MAX generate an error.
188 _POSIX_VDISABLE If defined, if the value of an element of the
189 `c_cc' member of `struct termios' is
190 _POSIX_VDISABLE, no character will have the
191 effect associated with that element.
192 _POSIX_SYNC_IO Synchronous I/O may be performed.
193 _POSIX_ASYNC_IO Asynchronous I/O may be performed.
194 _POSIX_PRIO_IO Prioritized Asynchronous I/O may be performed.
195
196 Support for the Large File Support interface is not generally available.
197 If it is available the following constants are defined to one.
198 _LFS64_LARGEFILE Low-level I/O supports large files.
199 _LFS64_STDIO Standard I/O supports large files.
200 */
201
202#include <bits/posix_opt.h>
203
204/* Get the environment definitions from Unix98. */
205#if defined __USE_UNIX98 || defined __USE_XOPEN2K
206# include <bits/environments.h>
207#endif
208
209/* Standard file descriptors. */
210#define STDIN_FILENO 0 /* Standard input. */
211#define STDOUT_FILENO 1 /* Standard output. */
212#define STDERR_FILENO 2 /* Standard error output. */
213
214
215/* All functions that are not declared anywhere else. */
216
217#include <bits/types.h>
218
219#ifndef __ssize_t_defined
220typedef __ssize_t ssize_t;
221# define __ssize_t_defined
222#endif
223
224#define __need_size_t
225#define __need_NULL
226#include <stddef.h>
227
228#if defined __USE_XOPEN || defined __USE_XOPEN2K
229/* The Single Unix specification says that some more types are
230 available here. */
231# ifndef __gid_t_defined
232typedef __gid_t gid_t;
233# define __gid_t_defined
234# endif
235
236# ifndef __uid_t_defined
237typedef __uid_t uid_t;
238# define __uid_t_defined
239# endif
240
241# ifndef __off_t_defined
242# ifndef __USE_FILE_OFFSET64
243typedef __off_t off_t;
244# else
245typedef __off64_t off_t;
246# endif
247# define __off_t_defined
248# endif
249# if defined __USE_LARGEFILE64 && !defined __off64_t_defined
250typedef __off64_t off64_t;
251# define __off64_t_defined
252# endif
253
254# ifndef __useconds_t_defined
255typedef __useconds_t useconds_t;
256# define __useconds_t_defined
257# endif
258
259# ifndef __pid_t_defined
260typedef __pid_t pid_t;
261# define __pid_t_defined
262# endif
263#endif /* X/Open */
264
265#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
266# ifndef __intptr_t_defined
267typedef __intptr_t intptr_t;
268# define __intptr_t_defined
269# endif
270#endif
271
272#if defined __USE_MISC || defined __USE_XOPEN
273# ifndef __socklen_t_defined
274typedef __socklen_t socklen_t;
275# define __socklen_t_defined
276# endif
277#endif
278
279/* Values for the second argument to access.
280 These may be OR'd together. */
281#define R_OK 4 /* Test for read permission. */
282#define W_OK 2 /* Test for write permission. */
283#define X_OK 1 /* Test for execute permission. */
284#define F_OK 0 /* Test for existence. */
285
286/* Test for access to NAME using the real UID and real GID. */
287extern int access (const char *__name, int __type) __THROW __nonnull ((1));
288
289#ifdef __USE_GNU
290/* Test for access to NAME using the effective UID and GID
291 (as normal file operations use). */
292extern int euidaccess (const char *__name, int __type)
293 __THROW __nonnull ((1));
294
295/* An alias for `euidaccess', used by some other systems. */
296extern int eaccess (const char *__name, int __type)
297 __THROW __nonnull ((1));
298#endif
299
300#ifdef __USE_ATFILE
301/* Test for access to FILE relative to the directory FD is open on.
302 If AT_EACCESS is set in FLAG, then use effective IDs like `eaccess',
303 otherwise use real IDs like `access'. */
304extern int faccessat (int __fd, const char *__file, int __type, int __flag)
305 __THROW __nonnull ((2)) __wur;
306#endif /* Use GNU. */
307
308
309/* Values for the WHENCE argument to lseek. */
310#ifndef _STDIO_H /* <stdio.h> has the same definitions. */
311# define SEEK_SET 0 /* Seek from beginning of file. */
312# define SEEK_CUR 1 /* Seek from current position. */
313# define SEEK_END 2 /* Seek from end of file. */
314# ifdef __USE_GNU
315# define SEEK_DATA 3 /* Seek to next data. */
316# define SEEK_HOLE 4 /* Seek to next hole. */
317# endif
318#endif
319
320#if defined __USE_MISC && !defined L_SET
321/* Old BSD names for the same constants; just for compatibility. */
322# define L_SET SEEK_SET
323# define L_INCR SEEK_CUR
324# define L_XTND SEEK_END
325#endif
326
327
328/* Move FD's file position to OFFSET bytes from the
329 beginning of the file (if WHENCE is SEEK_SET),
330 the current position (if WHENCE is SEEK_CUR),
331 or the end of the file (if WHENCE is SEEK_END).
332 Return the new file position. */
333#ifndef __USE_FILE_OFFSET64
334extern __off_t lseek (int __fd, __off_t __offset, int __whence) __THROW;
335#else
336# ifdef __REDIRECT_NTH
337extern __off64_t __REDIRECT_NTH (lseek,
338 (int __fd, __off64_t __offset, int __whence),
339 lseek64);
340# else
341# define lseek lseek64
342# endif
343#endif
344#ifdef __USE_LARGEFILE64
345extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence)
346 __THROW;
347#endif
348
349/* Close the file descriptor FD.
350
351 This function is a cancellation point and therefore not marked with
352 __THROW. */
353extern int close (int __fd);
354
355/* Read NBYTES into BUF from FD. Return the
356 number read, -1 for errors or 0 for EOF.
357
358 This function is a cancellation point and therefore not marked with
359 __THROW. */
360extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __wur;
361
362/* Write N bytes of BUF to FD. Return the number written, or -1.
363
364 This function is a cancellation point and therefore not marked with
365 __THROW. */
366extern ssize_t write (int __fd, const void *__buf, size_t __n) __wur;
367
368#if defined __USE_UNIX98 || defined __USE_XOPEN2K8
369# ifndef __USE_FILE_OFFSET64
370/* Read NBYTES into BUF from FD at the given position OFFSET without
371 changing the file pointer. Return the number read, -1 for errors
372 or 0 for EOF.
373
374 This function is a cancellation point and therefore not marked with
375 __THROW. */
376extern ssize_t pread (int __fd, void *__buf, size_t __nbytes,
377 __off_t __offset) __wur;
378
379/* Write N bytes of BUF to FD at the given position OFFSET without
380 changing the file pointer. Return the number written, or -1.
381
382 This function is a cancellation point and therefore not marked with
383 __THROW. */
384extern ssize_t pwrite (int __fd, const void *__buf, size_t __n,
385 __off_t __offset) __wur;
386# else
387# ifdef __REDIRECT
388extern ssize_t __REDIRECT (pread, (int __fd, void *__buf, size_t __nbytes,
389 __off64_t __offset),
390 pread64) __wur;
391extern ssize_t __REDIRECT (pwrite, (int __fd, const void *__buf,
392 size_t __nbytes, __off64_t __offset),
393 pwrite64) __wur;
394# else
395# define pread pread64
396# define pwrite pwrite64
397# endif
398# endif
399
400# ifdef __USE_LARGEFILE64
401/* Read NBYTES into BUF from FD at the given position OFFSET without
402 changing the file pointer. Return the number read, -1 for errors
403 or 0 for EOF. */
404extern ssize_t pread64 (int __fd, void *__buf, size_t __nbytes,
405 __off64_t __offset) __wur;
406/* Write N bytes of BUF to FD at the given position OFFSET without
407 changing the file pointer. Return the number written, or -1. */
408extern ssize_t pwrite64 (int __fd, const void *__buf, size_t __n,
409 __off64_t __offset) __wur;
410# endif
411#endif
412
413/* Create a one-way communication channel (pipe).
414 If successful, two file descriptors are stored in PIPEDES;
415 bytes written on PIPEDES[1] can be read from PIPEDES[0].
416 Returns 0 if successful, -1 if not. */
417extern int pipe (int __pipedes[2]) __THROW __wur;
418
419#ifdef __USE_GNU
420/* Same as pipe but apply flags passed in FLAGS to the new file
421 descriptors. */
422extern int pipe2 (int __pipedes[2], int __flags) __THROW __wur;
423#endif
424
425/* Schedule an alarm. In SECONDS seconds, the process will get a SIGALRM.
426 If SECONDS is zero, any currently scheduled alarm will be cancelled.
427 The function returns the number of seconds remaining until the last
428 alarm scheduled would have signaled, or zero if there wasn't one.
429 There is no return value to indicate an error, but you can set `errno'
430 to 0 and check its value after calling `alarm', and this might tell you.
431 The signal may come late due to processor scheduling. */
432extern unsigned int alarm (unsigned int __seconds) __THROW;
433
434/* Make the process sleep for SECONDS seconds, or until a signal arrives
435 and is not ignored. The function returns the number of seconds less
436 than SECONDS which it actually slept (thus zero if it slept the full time).
437 If a signal handler does a `longjmp' or modifies the handling of the
438 SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
439 signal afterwards is undefined. There is no return value to indicate
440 error, but if `sleep' returns SECONDS, it probably didn't work.
441
442 This function is a cancellation point and therefore not marked with
443 __THROW. */
444extern unsigned int sleep (unsigned int __seconds);
445
446#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
447 || defined __USE_MISC
448/* Set an alarm to go off (generating a SIGALRM signal) in VALUE
449 microseconds. If INTERVAL is nonzero, when the alarm goes off, the
450 timer is reset to go off every INTERVAL microseconds thereafter.
451 Returns the number of microseconds remaining before the alarm. */
452extern __useconds_t ualarm (__useconds_t __value, __useconds_t __interval)
453 __THROW;
454
455/* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
456 or ignored.
457
458 This function is a cancellation point and therefore not marked with
459 __THROW. */
460extern int usleep (__useconds_t __useconds);
461#endif
462
463
464/* Suspend the process until a signal arrives.
465 This always returns -1 and sets `errno' to EINTR.
466
467 This function is a cancellation point and therefore not marked with
468 __THROW. */
469extern int pause (void);
470
471
472/* Change the owner and group of FILE. */
473extern int chown (const char *__file, __uid_t __owner, __gid_t __group)
474 __THROW __nonnull ((1)) __wur;
475
476#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
477/* Change the owner and group of the file that FD is open on. */
478extern int fchown (int __fd, __uid_t __owner, __gid_t __group) __THROW __wur;
479
480
481/* Change owner and group of FILE, if it is a symbolic
482 link the ownership of the symbolic link is changed. */
483extern int lchown (const char *__file, __uid_t __owner, __gid_t __group)
484 __THROW __nonnull ((1)) __wur;
485
486#endif /* Use X/Open Unix. */
487
488#ifdef __USE_ATFILE
489/* Change the owner and group of FILE relative to the directory FD is open
490 on. */
491extern int fchownat (int __fd, const char *__file, __uid_t __owner,
492 __gid_t __group, int __flag)
493 __THROW __nonnull ((2)) __wur;
494#endif /* Use GNU. */
495
496/* Change the process's working directory to PATH. */
497extern int chdir (const char *__path) __THROW __nonnull ((1)) __wur;
498
499#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
500/* Change the process's working directory to the one FD is open on. */
501extern int fchdir (int __fd) __THROW __wur;
502#endif
503
504/* Get the pathname of the current working directory,
505 and put it in SIZE bytes of BUF. Returns NULL if the
506 directory couldn't be determined or SIZE was too small.
507 If successful, returns BUF. In GNU, if BUF is NULL,
508 an array is allocated with `malloc'; the array is SIZE
509 bytes long, unless SIZE == 0, in which case it is as
510 big as necessary. */
511extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
512
513#ifdef __USE_GNU
514/* Return a malloc'd string containing the current directory name.
515 If the environment variable `PWD' is set, and its value is correct,
516 that value is used. */
517extern char *get_current_dir_name (void) __THROW;
518#endif
519
520#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
521 || defined __USE_MISC
522/* Put the absolute pathname of the current working directory in BUF.
523 If successful, return BUF. If not, put an error message in
524 BUF and return NULL. BUF should be at least PATH_MAX bytes long. */
525extern char *getwd (char *__buf)
526 __THROW __nonnull ((1)) __attribute_deprecated__ __wur;
527#endif
528
529
530/* Duplicate FD, returning a new file descriptor on the same file. */
531extern int dup (int __fd) __THROW __wur;
532
533/* Duplicate FD to FD2, closing FD2 and making it open on the same file. */
534extern int dup2 (int __fd, int __fd2) __THROW;
535
536#ifdef __USE_GNU
537/* Duplicate FD to FD2, closing FD2 and making it open on the same
538 file while setting flags according to FLAGS. */
539extern int dup3 (int __fd, int __fd2, int __flags) __THROW;
540#endif
541
542/* NULL-terminated array of "NAME=VALUE" environment variables. */
543extern char **__environ;
544#ifdef __USE_GNU
545extern char **environ;
546#endif
547
548
549/* Replace the current process, executing PATH with arguments ARGV and
550 environment ENVP. ARGV and ENVP are terminated by NULL pointers. */
551extern int execve (const char *__path, char *const __argv[],
552 char *const __envp[]) __THROW __nonnull ((1, 2));
553
554#ifdef __USE_XOPEN2K8
555/* Execute the file FD refers to, overlaying the running program image.
556 ARGV and ENVP are passed to the new program, as for `execve'. */
557extern int fexecve (int __fd, char *const __argv[], char *const __envp[])
558 __THROW __nonnull ((2));
559#endif
560
561
562/* Execute PATH with arguments ARGV and environment from `environ'. */
563extern int execv (const char *__path, char *const __argv[])
564 __THROW __nonnull ((1, 2));
565
566/* Execute PATH with all arguments after PATH until a NULL pointer,
567 and the argument after that for environment. */
568extern int execle (const char *__path, const char *__arg, ...)
569 __THROW __nonnull ((1, 2));
570
571/* Execute PATH with all arguments after PATH until
572 a NULL pointer and environment from `environ'. */
573extern int execl (const char *__path, const char *__arg, ...)
574 __THROW __nonnull ((1, 2));
575
576/* Execute FILE, searching in the `PATH' environment variable if it contains
577 no slashes, with arguments ARGV and environment from `environ'. */
578extern int execvp (const char *__file, char *const __argv[])
579 __THROW __nonnull ((1, 2));
580
581/* Execute FILE, searching in the `PATH' environment variable if
582 it contains no slashes, with all arguments after FILE until a
583 NULL pointer and environment from `environ'. */
584extern int execlp (const char *__file, const char *__arg, ...)
585 __THROW __nonnull ((1, 2));
586
587#ifdef __USE_GNU
588/* Execute FILE, searching in the `PATH' environment variable if it contains
589 no slashes, with arguments ARGV and environment from `environ'. */
590extern int execvpe (const char *__file, char *const __argv[],
591 char *const __envp[])
592 __THROW __nonnull ((1, 2));
593#endif
594
595
596#if defined __USE_MISC || defined __USE_XOPEN
597/* Add INC to priority of the current process. */
598extern int nice (int __inc) __THROW __wur;
599#endif
600
601
602/* Terminate program execution with the low-order 8 bits of STATUS. */
603extern void _exit (int __status) __attribute__ ((__noreturn__));
604
605
606/* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
607 the `_SC_*' symbols for the NAME argument to `sysconf';
608 and the `_CS_*' symbols for the NAME argument to `confstr'. */
609#include <bits/confname.h>
610
611/* Get file-specific configuration information about PATH. */
612extern long int pathconf (const char *__path, int __name)
613 __THROW __nonnull ((1));
614
615/* Get file-specific configuration about descriptor FD. */
616extern long int fpathconf (int __fd, int __name) __THROW;
617
618/* Get the value of the system variable NAME. */
619extern long int sysconf (int __name) __THROW;
620
621#ifdef __USE_POSIX2
622/* Get the value of the string-valued system variable NAME. */
623extern size_t confstr (int __name, char *__buf, size_t __len) __THROW;
624#endif
625
626
627/* Get the process ID of the calling process. */
628extern __pid_t getpid (void) __THROW;
629
630/* Get the process ID of the calling process's parent. */
631extern __pid_t getppid (void) __THROW;
632
633/* Get the process group ID of the calling process. */
634extern __pid_t getpgrp (void) __THROW;
635
636/* Get the process group ID of process PID. */
637extern __pid_t __getpgid (__pid_t __pid) __THROW;
638#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
639extern __pid_t getpgid (__pid_t __pid) __THROW;
640#endif
641
642
643/* Set the process group ID of the process matching PID to PGID.
644 If PID is zero, the current process's process group ID is set.
645 If PGID is zero, the process ID of the process is used. */
646extern int setpgid (__pid_t __pid, __pid_t __pgid) __THROW;
647
648#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
649/* Both System V and BSD have `setpgrp' functions, but with different
650 calling conventions. The BSD function is the same as POSIX.1 `setpgid'
651 (above). The System V function takes no arguments and puts the calling
652 process in its on group like `setpgid (0, 0)'.
653
654 New programs should always use `setpgid' instead.
655
656 GNU provides the POSIX.1 function. */
657
658/* Set the process group ID of the calling process to its own PID.
659 This is exactly the same as `setpgid (0, 0)'. */
660extern int setpgrp (void) __THROW;
661
662#endif /* Use misc or X/Open. */
663
664/* Create a new session with the calling process as its leader.
665 The process group IDs of the session and the calling process
666 are set to the process ID of the calling process, which is returned. */
667extern __pid_t setsid (void) __THROW;
668
669#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
670/* Return the session ID of the given process. */
671extern __pid_t getsid (__pid_t __pid) __THROW;
672#endif
673
674/* Get the real user ID of the calling process. */
675extern __uid_t getuid (void) __THROW;
676
677/* Get the effective user ID of the calling process. */
678extern __uid_t geteuid (void) __THROW;
679
680/* Get the real group ID of the calling process. */
681extern __gid_t getgid (void) __THROW;
682
683/* Get the effective group ID of the calling process. */
684extern __gid_t getegid (void) __THROW;
685
686/* If SIZE is zero, return the number of supplementary groups
687 the calling process is in. Otherwise, fill in the group IDs
688 of its supplementary groups in LIST and return the number written. */
689extern int getgroups (int __size, __gid_t __list[]) __THROW __wur;
690
691#ifdef __USE_GNU
692/* Return nonzero iff the calling process is in group GID. */
693extern int group_member (__gid_t __gid) __THROW;
694#endif
695
696/* Set the user ID of the calling process to UID.
697 If the calling process is the super-user, set the real
698 and effective user IDs, and the saved set-user-ID to UID;
699 if not, the effective user ID is set to UID. */
700extern int setuid (__uid_t __uid) __THROW __wur;
701
702#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
703/* Set the real user ID of the calling process to RUID,
704 and the effective user ID of the calling process to EUID. */
705extern int setreuid (__uid_t __ruid, __uid_t __euid) __THROW __wur;
706#endif
707
708#ifdef __USE_XOPEN2K
709/* Set the effective user ID of the calling process to UID. */
710extern int seteuid (__uid_t __uid) __THROW __wur;
711#endif /* Use POSIX.1-2001. */
712
713/* Set the group ID of the calling process to GID.
714 If the calling process is the super-user, set the real
715 and effective group IDs, and the saved set-group-ID to GID;
716 if not, the effective group ID is set to GID. */
717extern int setgid (__gid_t __gid) __THROW __wur;
718
719#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
720/* Set the real group ID of the calling process to RGID,
721 and the effective group ID of the calling process to EGID. */
722extern int setregid (__gid_t __rgid, __gid_t __egid) __THROW __wur;
723#endif
724
725#ifdef __USE_XOPEN2K
726/* Set the effective group ID of the calling process to GID. */
727extern int setegid (__gid_t __gid) __THROW __wur;
728#endif /* Use POSIX.1-2001. */
729
730#ifdef __USE_GNU
731/* Fetch the real user ID, effective user ID, and saved-set user ID,
732 of the calling process. */
733extern int getresuid (__uid_t *__ruid, __uid_t *__euid, __uid_t *__suid)
734 __THROW;
735
736/* Fetch the real group ID, effective group ID, and saved-set group ID,
737 of the calling process. */
738extern int getresgid (__gid_t *__rgid, __gid_t *__egid, __gid_t *__sgid)
739 __THROW;
740
741/* Set the real user ID, effective user ID, and saved-set user ID,
742 of the calling process to RUID, EUID, and SUID, respectively. */
743extern int setresuid (__uid_t __ruid, __uid_t __euid, __uid_t __suid)
744 __THROW __wur;
745
746/* Set the real group ID, effective group ID, and saved-set group ID,
747 of the calling process to RGID, EGID, and SGID, respectively. */
748extern int setresgid (__gid_t __rgid, __gid_t __egid, __gid_t __sgid)
749 __THROW __wur;
750#endif
751
752
753/* Clone the calling process, creating an exact copy.
754 Return -1 for errors, 0 to the new process,
755 and the process ID of the new process to the old process. */
756extern __pid_t fork (void) __THROWNL;
757
758#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
759 || defined __USE_MISC
760/* Clone the calling process, but without copying the whole address space.
761 The calling process is suspended until the new process exits or is
762 replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
763 and the process ID of the new process to the old process. */
764extern __pid_t vfork (void) __THROW;
765#endif /* Use misc or XPG < 7. */
766
767
768/* Return the pathname of the terminal FD is open on, or NULL on errors.
769 The returned storage is good only until the next call to this function. */
770extern char *ttyname (int __fd) __THROW;
771
772/* Store at most BUFLEN characters of the pathname of the terminal FD is
773 open on in BUF. Return 0 on success, otherwise an error number. */
774extern int ttyname_r (int __fd, char *__buf, size_t __buflen)
775 __THROW __nonnull ((2)) __wur;
776
777/* Return 1 if FD is a valid descriptor associated
778 with a terminal, zero if not. */
779extern int isatty (int __fd) __THROW;
780
781#ifdef __USE_MISC
782/* Return the index into the active-logins file (utmp) for
783 the controlling terminal. */
784extern int ttyslot (void) __THROW;
785#endif
786
787
788/* Make a link to FROM named TO. */
789extern int link (const char *__from, const char *__to)
790 __THROW __nonnull ((1, 2)) __wur;
791
792#ifdef __USE_ATFILE
793/* Like link but relative paths in TO and FROM are interpreted relative
794 to FROMFD and TOFD respectively. */
795extern int linkat (int __fromfd, const char *__from, int __tofd,
796 const char *__to, int __flags)
797 __THROW __nonnull ((2, 4)) __wur;
798#endif
799
800#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
801/* Make a symbolic link to FROM named TO. */
802extern int symlink (const char *__from, const char *__to)
803 __THROW __nonnull ((1, 2)) __wur;
804
805/* Read the contents of the symbolic link PATH into no more than
806 LEN bytes of BUF. The contents are not null-terminated.
807 Returns the number of characters read, or -1 for errors. */
808extern ssize_t readlink (const char *__restrict __path,
809 char *__restrict __buf, size_t __len)
810 __THROW __nonnull ((1, 2)) __wur;
811#endif /* Use POSIX.1-2001. */
812
813#ifdef __USE_ATFILE
814/* Like symlink but a relative path in TO is interpreted relative to TOFD. */
815extern int symlinkat (const char *__from, int __tofd,
816 const char *__to) __THROW __nonnull ((1, 3)) __wur;
817
818/* Like readlink but a relative PATH is interpreted relative to FD. */
819extern ssize_t readlinkat (int __fd, const char *__restrict __path,
820 char *__restrict __buf, size_t __len)
821 __THROW __nonnull ((2, 3)) __wur;
822#endif
823
824/* Remove the link NAME. */
825extern int unlink (const char *__name) __THROW __nonnull ((1));
826
827#ifdef __USE_ATFILE
828/* Remove the link NAME relative to FD. */
829extern int unlinkat (int __fd, const char *__name, int __flag)
830 __THROW __nonnull ((2));
831#endif
832
833/* Remove the directory PATH. */
834extern int rmdir (const char *__path) __THROW __nonnull ((1));
835
836
837/* Return the foreground process group ID of FD. */
838extern __pid_t tcgetpgrp (int __fd) __THROW;
839
840/* Set the foreground process group ID of FD set PGRP_ID. */
841extern int tcsetpgrp (int __fd, __pid_t __pgrp_id) __THROW;
842
843
844/* Return the login name of the user.
845
846 This function is a possible cancellation point and therefore not
847 marked with __THROW. */
848extern char *getlogin (void);
849#ifdef __USE_POSIX199506
850/* Return at most NAME_LEN characters of the login name of the user in NAME.
851 If it cannot be determined or some other error occurred, return the error
852 code. Otherwise return 0.
853
854 This function is a possible cancellation point and therefore not
855 marked with __THROW. */
856extern int getlogin_r (char *__name, size_t __name_len) __nonnull ((1));
857#endif
858
859#ifdef __USE_MISC
860/* Set the login name returned by `getlogin'. */
861extern int setlogin (const char *__name) __THROW __nonnull ((1));
862#endif
863
864
865#ifdef __USE_POSIX2
866/* Get definitions and prototypes for functions to process the
867 arguments in ARGV (ARGC of them, minus the program name) for
868 options given in OPTS. */
869# include <bits/getopt_posix.h>
870#endif
871
872
873#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
874/* Put the name of the current host in no more than LEN bytes of NAME.
875 The result is null-terminated if LEN is large enough for the full
876 name and the terminator. */
877extern int gethostname (char *__name, size_t __len) __THROW __nonnull ((1));
878#endif
879
880
881#if defined __USE_MISC
882/* Set the name of the current host to NAME, which is LEN bytes long.
883 This call is restricted to the super-user. */
884extern int sethostname (const char *__name, size_t __len)
885 __THROW __nonnull ((1)) __wur;
886
887/* Set the current machine's Internet number to ID.
888 This call is restricted to the super-user. */
889extern int sethostid (long int __id) __THROW __wur;
890
891
892/* Get and set the NIS (aka YP) domain name, if any.
893 Called just like `gethostname' and `sethostname'.
894 The NIS domain name is usually the empty string when not using NIS. */
895extern int getdomainname (char *__name, size_t __len)
896 __THROW __nonnull ((1)) __wur;
897extern int setdomainname (const char *__name, size_t __len)
898 __THROW __nonnull ((1)) __wur;
899
900
901/* Revoke access permissions to all processes currently communicating
902 with the control terminal, and then send a SIGHUP signal to the process
903 group of the control terminal. */
904extern int vhangup (void) __THROW;
905
906/* Revoke the access of all descriptors currently open on FILE. */
907extern int revoke (const char *__file) __THROW __nonnull ((1)) __wur;
908
909
910/* Enable statistical profiling, writing samples of the PC into at most
911 SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
912 is enabled, the system examines the user PC and increments
913 SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536]. If SCALE is zero,
914 disable profiling. Returns zero on success, -1 on error. */
915extern int profil (unsigned short int *__sample_buffer, size_t __size,
916 size_t __offset, unsigned int __scale)
917 __THROW __nonnull ((1));
918
919
920/* Turn accounting on if NAME is an existing file. The system will then write
921 a record for each process as it terminates, to this file. If NAME is NULL,
922 turn accounting off. This call is restricted to the super-user. */
923extern int acct (const char *__name) __THROW;
924
925
926/* Successive calls return the shells listed in `/etc/shells'. */
927extern char *getusershell (void) __THROW;
928extern void endusershell (void) __THROW; /* Discard cached info. */
929extern void setusershell (void) __THROW; /* Rewind and re-read the file. */
930
931
932/* Put the program in the background, and dissociate from the controlling
933 terminal. If NOCHDIR is zero, do `chdir ("/")'. If NOCLOSE is zero,
934 redirects stdin, stdout, and stderr to /dev/null. */
935extern int daemon (int __nochdir, int __noclose) __THROW __wur;
936#endif /* Use misc. */
937
938
939#if defined __USE_MISC || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
940/* Make PATH be the root directory (the starting point for absolute paths).
941 This call is restricted to the super-user. */
942extern int chroot (const char *__path) __THROW __nonnull ((1)) __wur;
943
944/* Prompt with PROMPT and read a string from the terminal without echoing.
945 Uses /dev/tty if possible; otherwise stderr and stdin. */
946extern char *getpass (const char *__prompt) __nonnull ((1));
947#endif /* Use misc || X/Open. */
948
949
950/* Make all changes done to FD actually appear on disk.
951
952 This function is a cancellation point and therefore not marked with
953 __THROW. */
954extern int fsync (int __fd);
955
956
957#ifdef __USE_GNU
958/* Make all changes done to all files on the file system associated
959 with FD actually appear on disk. */
960extern int syncfs (int __fd) __THROW;
961#endif
962
963
964#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
965
966/* Return identifier for the current host. */
967extern long int gethostid (void);
968
969/* Make all changes done to all files actually appear on disk. */
970extern void sync (void) __THROW;
971
972
973# if defined __USE_MISC || !defined __USE_XOPEN2K
974/* Return the number of bytes in a page. This is the system's page size,
975 which is not necessarily the same as the hardware page size. */
976extern int getpagesize (void) __THROW __attribute__ ((__const__));
977
978
979/* Return the maximum number of file descriptors
980 the current process could possibly have. */
981extern int getdtablesize (void) __THROW;
982# endif
983
984#endif /* Use misc || X/Open Unix. */
985
986
987#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
988
989/* Truncate FILE to LENGTH bytes. */
990# ifndef __USE_FILE_OFFSET64
991extern int truncate (const char *__file, __off_t __length)
992 __THROW __nonnull ((1)) __wur;
993# else
994# ifdef __REDIRECT_NTH
995extern int __REDIRECT_NTH (truncate,
996 (const char *__file, __off64_t __length),
997 truncate64) __nonnull ((1)) __wur;
998# else
999# define truncate truncate64
1000# endif
1001# endif
1002# ifdef __USE_LARGEFILE64
1003extern int truncate64 (const char *__file, __off64_t __length)
1004 __THROW __nonnull ((1)) __wur;
1005# endif
1006
1007#endif /* Use X/Open Unix || POSIX 2008. */
1008
1009#if defined __USE_POSIX199309 \
1010 || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
1011
1012/* Truncate the file FD is open on to LENGTH bytes. */
1013# ifndef __USE_FILE_OFFSET64
1014extern int ftruncate (int __fd, __off_t __length) __THROW __wur;
1015# else
1016# ifdef __REDIRECT_NTH
1017extern int __REDIRECT_NTH (ftruncate, (int __fd, __off64_t __length),
1018 ftruncate64) __wur;
1019# else
1020# define ftruncate ftruncate64
1021# endif
1022# endif
1023# ifdef __USE_LARGEFILE64
1024extern int ftruncate64 (int __fd, __off64_t __length) __THROW __wur;
1025# endif
1026
1027#endif /* Use POSIX.1b || X/Open Unix || XPG6. */
1028
1029
1030#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K) \
1031 || defined __USE_MISC
1032
1033/* Set the end of accessible data space (aka "the break") to ADDR.
1034 Returns zero on success and -1 for errors (with errno set). */
1035extern int brk (void *__addr) __THROW __wur;
1036
1037/* Increase or decrease the end of accessible data space by DELTA bytes.
1038 If successful, returns the address the previous end of data space
1039 (i.e. the beginning of the new space, if DELTA > 0);
1040 returns (void *) -1 for errors (with errno set). */
1041extern void *sbrk (intptr_t __delta) __THROW;
1042#endif
1043
1044
1045#ifdef __USE_MISC
1046/* Invoke `system call' number SYSNO, passing it the remaining arguments.
1047 This is completely system-dependent, and not often useful.
1048
1049 In Unix, `syscall' sets `errno' for all errors and most calls return -1
1050 for errors; in many systems you cannot pass arguments or get return
1051 values for all system calls (`pipe', `fork', and `getppid' typically
1052 among them).
1053
1054 In Mach, all system calls take normal arguments and always return an
1055 error code (zero for success). */
1056extern long int syscall (long int __sysno, ...) __THROW;
1057
1058#endif /* Use misc. */
1059
1060
1061#if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
1062/* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
1063 files consistent. Some systems have them there and some here, and some
1064 software depends on the macros being defined without including both. */
1065
1066/* `lockf' is a simpler interface to the locking facilities of `fcntl'.
1067 LEN is always relative to the current file position.
1068 The CMD argument is one of the following.
1069
1070 This function is a cancellation point and therefore not marked with
1071 __THROW. */
1072
1073# define F_ULOCK 0 /* Unlock a previously locked region. */
1074# define F_LOCK 1 /* Lock a region for exclusive use. */
1075# define F_TLOCK 2 /* Test and lock a region for exclusive use. */
1076# define F_TEST 3 /* Test a region for other processes locks. */
1077
1078# ifndef __USE_FILE_OFFSET64
1079extern int lockf (int __fd, int __cmd, __off_t __len) __wur;
1080# else
1081# ifdef __REDIRECT
1082extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len),
1083 lockf64) __wur;
1084# else
1085# define lockf lockf64
1086# endif
1087# endif
1088# ifdef __USE_LARGEFILE64
1089extern int lockf64 (int __fd, int __cmd, __off64_t __len) __wur;
1090# endif
1091#endif /* Use misc and F_LOCK not already defined. */
1092
1093
1094#ifdef __USE_GNU
1095
1096/* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
1097 set to EINTR. */
1098
1099# define TEMP_FAILURE_RETRY(expression) \
1100 (__extension__ \
1101 ({ long int __result; \
1102 do __result = (long int) (expression); \
1103 while (__result == -1L && errno == EINTR); \
1104 __result; }))
1105
1106/* Copy LENGTH bytes from INFD to OUTFD. */
1107ssize_t copy_file_range (int __infd, __off64_t *__pinoff,
1108 int __outfd, __off64_t *__poutoff,
1109 size_t __length, unsigned int __flags);
1110#endif /* __USE_GNU */
1111
1112#if defined __USE_POSIX199309 || defined __USE_UNIX98
1113/* Synchronize at least the data part of a file with the underlying
1114 media. */
1115extern int fdatasync (int __fildes);
1116#endif /* Use POSIX199309 */
1117
1118#ifdef __USE_MISC
1119/* One-way hash PHRASE, returning a string suitable for storage in the
1120 user database. SALT selects the one-way function to use, and
1121 ensures that no two users' hashes are the same, even if they use
1122 the same passphrase. The return value points to static storage
1123 which will be overwritten by the next call to crypt. */
1124extern char *crypt (const char *__key, const char *__salt)
1125 __THROW __nonnull ((1, 2));
1126#endif
1127
1128#ifdef __USE_XOPEN
1129/* Swab pairs bytes in the first N bytes of the area pointed to by
1130 FROM and copy the result to TO. The value of TO must not be in the
1131 range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
1132 is without partner. */
1133extern void swab (const void *__restrict __from, void *__restrict __to,
1134 ssize_t __n) __THROW __nonnull ((1, 2));
1135#endif
1136
1137
1138/* Prior to Issue 6, the Single Unix Specification required these
1139 prototypes to appear in this header. They are also found in
1140 <stdio.h>. */
1141#if defined __USE_XOPEN && !defined __USE_XOPEN2K
1142/* Return the name of the controlling terminal. */
1143extern char *ctermid (char *__s) __THROW;
1144
1145/* Return the name of the current user. */
1146extern char *cuserid (char *__s);
1147#endif
1148
1149
1150/* Unix98 requires this function to be declared here. In other
1151 standards it is in <pthread.h>. */
1152#if defined __USE_UNIX98 && !defined __USE_XOPEN2K
1153extern int pthread_atfork (void (*__prepare) (void),
1154 void (*__parent) (void),
1155 void (*__child) (void)) __THROW;
1156#endif
1157
1158#ifdef __USE_MISC
1159/* Write LENGTH bytes of randomness starting at BUFFER. Return 0 on
1160 success or -1 on error. */
1161int getentropy (void *__buffer, size_t __length) __wur;
1162#endif
1163
1164/* Define some macros helping to catch buffer overflows. */
1165#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
1166# include <bits/unistd.h>
1167#endif
1168
1169/* System-specific extensions. */
1170#include <bits/unistd_ext.h>
1171
1172__END_DECLS
1173
1174#endif /* unistd.h */
1175

source code of include/unistd.h