1/* Copyright (C) 1991-2018 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 <http://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/* Encryption is present. */
111#define _XOPEN_CRYPT 1
112
113/* The enhanced internationalization capabilities according to XPG4.2
114 are present. */
115#define _XOPEN_ENH_I18N 1
116
117/* The legacy interfaces are also available. */
118#define _XOPEN_LEGACY 1
119
120
121/* Get values of POSIX options:
122
123 If these symbols are defined, the corresponding features are
124 always available. If not, they may be available sometimes.
125 The current values can be obtained with `sysconf'.
126
127 _POSIX_JOB_CONTROL Job control is supported.
128 _POSIX_SAVED_IDS Processes have a saved set-user-ID
129 and a saved set-group-ID.
130 _POSIX_REALTIME_SIGNALS Real-time, queued signals are supported.
131 _POSIX_PRIORITY_SCHEDULING Priority scheduling is supported.
132 _POSIX_TIMERS POSIX.4 clocks and timers are supported.
133 _POSIX_ASYNCHRONOUS_IO Asynchronous I/O is supported.
134 _POSIX_PRIORITIZED_IO Prioritized asynchronous I/O is supported.
135 _POSIX_SYNCHRONIZED_IO Synchronizing file data is supported.
136 _POSIX_FSYNC The fsync function is present.
137 _POSIX_MAPPED_FILES Mapping of files to memory is supported.
138 _POSIX_MEMLOCK Locking of all memory is supported.
139 _POSIX_MEMLOCK_RANGE Locking of ranges of memory is supported.
140 _POSIX_MEMORY_PROTECTION Setting of memory protections is supported.
141 _POSIX_MESSAGE_PASSING POSIX.4 message queues are supported.
142 _POSIX_SEMAPHORES POSIX.4 counting semaphores are supported.
143 _POSIX_SHARED_MEMORY_OBJECTS POSIX.4 shared memory objects are supported.
144 _POSIX_THREADS POSIX.1c pthreads are supported.
145 _POSIX_THREAD_ATTR_STACKADDR Thread stack address attribute option supported.
146 _POSIX_THREAD_ATTR_STACKSIZE Thread stack size attribute option supported.
147 _POSIX_THREAD_SAFE_FUNCTIONS Thread-safe functions are supported.
148 _POSIX_THREAD_PRIORITY_SCHEDULING
149 POSIX.1c thread execution scheduling supported.
150 _POSIX_THREAD_PRIO_INHERIT Thread priority inheritance option supported.
151 _POSIX_THREAD_PRIO_PROTECT Thread priority protection option supported.
152 _POSIX_THREAD_PROCESS_SHARED Process-shared synchronization supported.
153 _POSIX_PII Protocol-independent interfaces are supported.
154 _POSIX_PII_XTI XTI protocol-indep. interfaces are supported.
155 _POSIX_PII_SOCKET Socket protocol-indep. interfaces are supported.
156 _POSIX_PII_INTERNET Internet family of protocols supported.
157 _POSIX_PII_INTERNET_STREAM Connection-mode Internet protocol supported.
158 _POSIX_PII_INTERNET_DGRAM Connectionless Internet protocol supported.
159 _POSIX_PII_OSI ISO/OSI family of protocols supported.
160 _POSIX_PII_OSI_COTS Connection-mode ISO/OSI service supported.
161 _POSIX_PII_OSI_CLTS Connectionless ISO/OSI service supported.
162 _POSIX_POLL Implementation supports `poll' function.
163 _POSIX_SELECT Implementation supports `select' and `pselect'.
164
165 _XOPEN_REALTIME X/Open realtime support is available.
166 _XOPEN_REALTIME_THREADS X/Open realtime thread support is available.
167 _XOPEN_SHM Shared memory interface according to XPG4.2.
168
169 _XBS5_ILP32_OFF32 Implementation provides environment with 32-bit
170 int, long, pointer, and off_t types.
171 _XBS5_ILP32_OFFBIG Implementation provides environment with 32-bit
172 int, long, and pointer and off_t with at least
173 64 bits.
174 _XBS5_LP64_OFF64 Implementation provides environment with 32-bit
175 int, and 64-bit long, pointer, and off_t types.
176 _XBS5_LPBIG_OFFBIG Implementation provides environment with at
177 least 32 bits int and long, pointer, and off_t
178 with at least 64 bits.
179
180 If any of these symbols is defined as -1, the corresponding option is not
181 true for any file. If any is defined as other than -1, the corresponding
182 option is true for all files. If a symbol is not defined at all, the value
183 for a specific file can be obtained from `pathconf' and `fpathconf'.
184
185 _POSIX_CHOWN_RESTRICTED Only the super user can use `chown' to change
186 the owner of a file. `chown' can only be used
187 to change the group ID of a file to a group of
188 which the calling process is a member.
189 _POSIX_NO_TRUNC Pathname components longer than
190 NAME_MAX generate an error.
191 _POSIX_VDISABLE If defined, if the value of an element of the
192 `c_cc' member of `struct termios' is
193 _POSIX_VDISABLE, no character will have the
194 effect associated with that element.
195 _POSIX_SYNC_IO Synchronous I/O may be performed.
196 _POSIX_ASYNC_IO Asynchronous I/O may be performed.
197 _POSIX_PRIO_IO Prioritized Asynchronous I/O may be performed.
198
199 Support for the Large File Support interface is not generally available.
200 If it is available the following constants are defined to one.
201 _LFS64_LARGEFILE Low-level I/O supports large files.
202 _LFS64_STDIO Standard I/O supports large files.
203 */
204
205#include <bits/posix_opt.h>
206
207/* Get the environment definitions from Unix98. */
208#if defined __USE_UNIX98 || defined __USE_XOPEN2K
209# include <bits/environments.h>
210#endif
211
212/* Standard file descriptors. */
213#define STDIN_FILENO 0 /* Standard input. */
214#define STDOUT_FILENO 1 /* Standard output. */
215#define STDERR_FILENO 2 /* Standard error output. */
216
217
218/* All functions that are not declared anywhere else. */
219
220#include <bits/types.h>
221
222#ifndef __ssize_t_defined
223typedef __ssize_t ssize_t;
224# define __ssize_t_defined
225#endif
226
227#define __need_size_t
228#define __need_NULL
229#include <stddef.h>
230
231#if defined __USE_XOPEN || defined __USE_XOPEN2K
232/* The Single Unix specification says that some more types are
233 available here. */
234# ifndef __gid_t_defined
235typedef __gid_t gid_t;
236# define __gid_t_defined
237# endif
238
239# ifndef __uid_t_defined
240typedef __uid_t uid_t;
241# define __uid_t_defined
242# endif
243
244# ifndef __off_t_defined
245# ifndef __USE_FILE_OFFSET64
246typedef __off_t off_t;
247# else
248typedef __off64_t off_t;
249# endif
250# define __off_t_defined
251# endif
252# if defined __USE_LARGEFILE64 && !defined __off64_t_defined
253typedef __off64_t off64_t;
254# define __off64_t_defined
255# endif
256
257# ifndef __useconds_t_defined
258typedef __useconds_t useconds_t;
259# define __useconds_t_defined
260# endif
261
262# ifndef __pid_t_defined
263typedef __pid_t pid_t;
264# define __pid_t_defined
265# endif
266#endif /* X/Open */
267
268#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
269# ifndef __intptr_t_defined
270typedef __intptr_t intptr_t;
271# define __intptr_t_defined
272# endif
273#endif
274
275#if defined __USE_MISC || defined __USE_XOPEN
276# ifndef __socklen_t_defined
277typedef __socklen_t socklen_t;
278# define __socklen_t_defined
279# endif
280#endif
281
282/* Values for the second argument to access.
283 These may be OR'd together. */
284#define R_OK 4 /* Test for read permission. */
285#define W_OK 2 /* Test for write permission. */
286#define X_OK 1 /* Test for execute permission. */
287#define F_OK 0 /* Test for existence. */
288
289/* Test for access to NAME using the real UID and real GID. */
290extern int access (const char *__name, int __type) __THROW __nonnull ((1));
291
292#ifdef __USE_GNU
293/* Test for access to NAME using the effective UID and GID
294 (as normal file operations use). */
295extern int euidaccess (const char *__name, int __type)
296 __THROW __nonnull ((1));
297
298/* An alias for `euidaccess', used by some other systems. */
299extern int eaccess (const char *__name, int __type)
300 __THROW __nonnull ((1));
301#endif
302
303#ifdef __USE_ATFILE
304/* Test for access to FILE relative to the directory FD is open on.
305 If AT_EACCESS is set in FLAG, then use effective IDs like `eaccess',
306 otherwise use real IDs like `access'. */
307extern int faccessat (int __fd, const char *__file, int __type, int __flag)
308 __THROW __nonnull ((2)) __wur;
309#endif /* Use GNU. */
310
311
312/* Values for the WHENCE argument to lseek. */
313#ifndef _STDIO_H /* <stdio.h> has the same definitions. */
314# define SEEK_SET 0 /* Seek from beginning of file. */
315# define SEEK_CUR 1 /* Seek from current position. */
316# define SEEK_END 2 /* Seek from end of file. */
317# ifdef __USE_GNU
318# define SEEK_DATA 3 /* Seek to next data. */
319# define SEEK_HOLE 4 /* Seek to next hole. */
320# endif
321#endif
322
323#if defined __USE_MISC && !defined L_SET
324/* Old BSD names for the same constants; just for compatibility. */
325# define L_SET SEEK_SET
326# define L_INCR SEEK_CUR
327# define L_XTND SEEK_END
328#endif
329
330
331/* Move FD's file position to OFFSET bytes from the
332 beginning of the file (if WHENCE is SEEK_SET),
333 the current position (if WHENCE is SEEK_CUR),
334 or the end of the file (if WHENCE is SEEK_END).
335 Return the new file position. */
336#ifndef __USE_FILE_OFFSET64
337extern __off_t lseek (int __fd, __off_t __offset, int __whence) __THROW;
338#else
339# ifdef __REDIRECT_NTH
340extern __off64_t __REDIRECT_NTH (lseek,
341 (int __fd, __off64_t __offset, int __whence),
342 lseek64);
343# else
344# define lseek lseek64
345# endif
346#endif
347#ifdef __USE_LARGEFILE64
348extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence)
349 __THROW;
350#endif
351
352/* Close the file descriptor FD.
353
354 This function is a cancellation point and therefore not marked with
355 __THROW. */
356extern int close (int __fd);
357
358/* Read NBYTES into BUF from FD. Return the
359 number read, -1 for errors or 0 for EOF.
360
361 This function is a cancellation point and therefore not marked with
362 __THROW. */
363extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __wur;
364
365/* Write N bytes of BUF to FD. Return the number written, or -1.
366
367 This function is a cancellation point and therefore not marked with
368 __THROW. */
369extern ssize_t write (int __fd, const void *__buf, size_t __n) __wur;
370
371#if defined __USE_UNIX98 || defined __USE_XOPEN2K8
372# ifndef __USE_FILE_OFFSET64
373/* Read NBYTES into BUF from FD at the given position OFFSET without
374 changing the file pointer. Return the number read, -1 for errors
375 or 0 for EOF.
376
377 This function is a cancellation point and therefore not marked with
378 __THROW. */
379extern ssize_t pread (int __fd, void *__buf, size_t __nbytes,
380 __off_t __offset) __wur;
381
382/* Write N bytes of BUF to FD at the given position OFFSET without
383 changing the file pointer. Return the number written, or -1.
384
385 This function is a cancellation point and therefore not marked with
386 __THROW. */
387extern ssize_t pwrite (int __fd, const void *__buf, size_t __n,
388 __off_t __offset) __wur;
389# else
390# ifdef __REDIRECT
391extern ssize_t __REDIRECT (pread, (int __fd, void *__buf, size_t __nbytes,
392 __off64_t __offset),
393 pread64) __wur;
394extern ssize_t __REDIRECT (pwrite, (int __fd, const void *__buf,
395 size_t __nbytes, __off64_t __offset),
396 pwrite64) __wur;
397# else
398# define pread pread64
399# define pwrite pwrite64
400# endif
401# endif
402
403# ifdef __USE_LARGEFILE64
404/* Read NBYTES into BUF from FD at the given position OFFSET without
405 changing the file pointer. Return the number read, -1 for errors
406 or 0 for EOF. */
407extern ssize_t pread64 (int __fd, void *__buf, size_t __nbytes,
408 __off64_t __offset) __wur;
409/* Write N bytes of BUF to FD at the given position OFFSET without
410 changing the file pointer. Return the number written, or -1. */
411extern ssize_t pwrite64 (int __fd, const void *__buf, size_t __n,
412 __off64_t __offset) __wur;
413# endif
414#endif
415
416/* Create a one-way communication channel (pipe).
417 If successful, two file descriptors are stored in PIPEDES;
418 bytes written on PIPEDES[1] can be read from PIPEDES[0].
419 Returns 0 if successful, -1 if not. */
420extern int pipe (int __pipedes[2]) __THROW __wur;
421
422#ifdef __USE_GNU
423/* Same as pipe but apply flags passed in FLAGS to the new file
424 descriptors. */
425extern int pipe2 (int __pipedes[2], int __flags) __THROW __wur;
426#endif
427
428/* Schedule an alarm. In SECONDS seconds, the process will get a SIGALRM.
429 If SECONDS is zero, any currently scheduled alarm will be cancelled.
430 The function returns the number of seconds remaining until the last
431 alarm scheduled would have signaled, or zero if there wasn't one.
432 There is no return value to indicate an error, but you can set `errno'
433 to 0 and check its value after calling `alarm', and this might tell you.
434 The signal may come late due to processor scheduling. */
435extern unsigned int alarm (unsigned int __seconds) __THROW;
436
437/* Make the process sleep for SECONDS seconds, or until a signal arrives
438 and is not ignored. The function returns the number of seconds less
439 than SECONDS which it actually slept (thus zero if it slept the full time).
440 If a signal handler does a `longjmp' or modifies the handling of the
441 SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
442 signal afterwards is undefined. There is no return value to indicate
443 error, but if `sleep' returns SECONDS, it probably didn't work.
444
445 This function is a cancellation point and therefore not marked with
446 __THROW. */
447extern unsigned int sleep (unsigned int __seconds);
448
449#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
450 || defined __USE_MISC
451/* Set an alarm to go off (generating a SIGALRM signal) in VALUE
452 microseconds. If INTERVAL is nonzero, when the alarm goes off, the
453 timer is reset to go off every INTERVAL microseconds thereafter.
454 Returns the number of microseconds remaining before the alarm. */
455extern __useconds_t ualarm (__useconds_t __value, __useconds_t __interval)
456 __THROW;
457
458/* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
459 or ignored.
460
461 This function is a cancellation point and therefore not marked with
462 __THROW. */
463extern int usleep (__useconds_t __useconds);
464#endif
465
466
467/* Suspend the process until a signal arrives.
468 This always returns -1 and sets `errno' to EINTR.
469
470 This function is a cancellation point and therefore not marked with
471 __THROW. */
472extern int pause (void);
473
474
475/* Change the owner and group of FILE. */
476extern int chown (const char *__file, __uid_t __owner, __gid_t __group)
477 __THROW __nonnull ((1)) __wur;
478
479#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
480/* Change the owner and group of the file that FD is open on. */
481extern int fchown (int __fd, __uid_t __owner, __gid_t __group) __THROW __wur;
482
483
484/* Change owner and group of FILE, if it is a symbolic
485 link the ownership of the symbolic link is changed. */
486extern int lchown (const char *__file, __uid_t __owner, __gid_t __group)
487 __THROW __nonnull ((1)) __wur;
488
489#endif /* Use X/Open Unix. */
490
491#ifdef __USE_ATFILE
492/* Change the owner and group of FILE relative to the directory FD is open
493 on. */
494extern int fchownat (int __fd, const char *__file, __uid_t __owner,
495 __gid_t __group, int __flag)
496 __THROW __nonnull ((2)) __wur;
497#endif /* Use GNU. */
498
499/* Change the process's working directory to PATH. */
500extern int chdir (const char *__path) __THROW __nonnull ((1)) __wur;
501
502#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
503/* Change the process's working directory to the one FD is open on. */
504extern int fchdir (int __fd) __THROW __wur;
505#endif
506
507/* Get the pathname of the current working directory,
508 and put it in SIZE bytes of BUF. Returns NULL if the
509 directory couldn't be determined or SIZE was too small.
510 If successful, returns BUF. In GNU, if BUF is NULL,
511 an array is allocated with `malloc'; the array is SIZE
512 bytes long, unless SIZE == 0, in which case it is as
513 big as necessary. */
514extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
515
516#ifdef __USE_GNU
517/* Return a malloc'd string containing the current directory name.
518 If the environment variable `PWD' is set, and its value is correct,
519 that value is used. */
520extern char *get_current_dir_name (void) __THROW;
521#endif
522
523#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
524 || defined __USE_MISC
525/* Put the absolute pathname of the current working directory in BUF.
526 If successful, return BUF. If not, put an error message in
527 BUF and return NULL. BUF should be at least PATH_MAX bytes long. */
528extern char *getwd (char *__buf)
529 __THROW __nonnull ((1)) __attribute_deprecated__ __wur;
530#endif
531
532
533/* Duplicate FD, returning a new file descriptor on the same file. */
534extern int dup (int __fd) __THROW __wur;
535
536/* Duplicate FD to FD2, closing FD2 and making it open on the same file. */
537extern int dup2 (int __fd, int __fd2) __THROW;
538
539#ifdef __USE_GNU
540/* Duplicate FD to FD2, closing FD2 and making it open on the same
541 file while setting flags according to FLAGS. */
542extern int dup3 (int __fd, int __fd2, int __flags) __THROW;
543#endif
544
545/* NULL-terminated array of "NAME=VALUE" environment variables. */
546extern char **__environ;
547#ifdef __USE_GNU
548extern char **environ;
549#endif
550
551
552/* Replace the current process, executing PATH with arguments ARGV and
553 environment ENVP. ARGV and ENVP are terminated by NULL pointers. */
554extern int execve (const char *__path, char *const __argv[],
555 char *const __envp[]) __THROW __nonnull ((1, 2));
556
557#ifdef __USE_XOPEN2K8
558/* Execute the file FD refers to, overlaying the running program image.
559 ARGV and ENVP are passed to the new program, as for `execve'. */
560extern int fexecve (int __fd, char *const __argv[], char *const __envp[])
561 __THROW __nonnull ((2));
562#endif
563
564
565/* Execute PATH with arguments ARGV and environment from `environ'. */
566extern int execv (const char *__path, char *const __argv[])
567 __THROW __nonnull ((1, 2));
568
569/* Execute PATH with all arguments after PATH until a NULL pointer,
570 and the argument after that for environment. */
571extern int execle (const char *__path, const char *__arg, ...)
572 __THROW __nonnull ((1, 2));
573
574/* Execute PATH with all arguments after PATH until
575 a NULL pointer and environment from `environ'. */
576extern int execl (const char *__path, const char *__arg, ...)
577 __THROW __nonnull ((1, 2));
578
579/* Execute FILE, searching in the `PATH' environment variable if it contains
580 no slashes, with arguments ARGV and environment from `environ'. */
581extern int execvp (const char *__file, char *const __argv[])
582 __THROW __nonnull ((1, 2));
583
584/* Execute FILE, searching in the `PATH' environment variable if
585 it contains no slashes, with all arguments after FILE until a
586 NULL pointer and environment from `environ'. */
587extern int execlp (const char *__file, const char *__arg, ...)
588 __THROW __nonnull ((1, 2));
589
590#ifdef __USE_GNU
591/* Execute FILE, searching in the `PATH' environment variable if it contains
592 no slashes, with arguments ARGV and environment from `environ'. */
593extern int execvpe (const char *__file, char *const __argv[],
594 char *const __envp[])
595 __THROW __nonnull ((1, 2));
596#endif
597
598
599#if defined __USE_MISC || defined __USE_XOPEN
600/* Add INC to priority of the current process. */
601extern int nice (int __inc) __THROW __wur;
602#endif
603
604
605/* Terminate program execution with the low-order 8 bits of STATUS. */
606extern void _exit (int __status) __attribute__ ((__noreturn__));
607
608
609/* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
610 the `_SC_*' symbols for the NAME argument to `sysconf';
611 and the `_CS_*' symbols for the NAME argument to `confstr'. */
612#include <bits/confname.h>
613
614/* Get file-specific configuration information about PATH. */
615extern long int pathconf (const char *__path, int __name)
616 __THROW __nonnull ((1));
617
618/* Get file-specific configuration about descriptor FD. */
619extern long int fpathconf (int __fd, int __name) __THROW;
620
621/* Get the value of the system variable NAME. */
622extern long int sysconf (int __name) __THROW;
623
624#ifdef __USE_POSIX2
625/* Get the value of the string-valued system variable NAME. */
626extern size_t confstr (int __name, char *__buf, size_t __len) __THROW;
627#endif
628
629
630/* Get the process ID of the calling process. */
631extern __pid_t getpid (void) __THROW;
632
633/* Get the process ID of the calling process's parent. */
634extern __pid_t getppid (void) __THROW;
635
636/* Get the process group ID of the calling process. */
637extern __pid_t getpgrp (void) __THROW;
638
639/* Get the process group ID of process PID. */
640extern __pid_t __getpgid (__pid_t __pid) __THROW;
641#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
642extern __pid_t getpgid (__pid_t __pid) __THROW;
643#endif
644
645
646/* Set the process group ID of the process matching PID to PGID.
647 If PID is zero, the current process's process group ID is set.
648 If PGID is zero, the process ID of the process is used. */
649extern int setpgid (__pid_t __pid, __pid_t __pgid) __THROW;
650
651#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
652/* Both System V and BSD have `setpgrp' functions, but with different
653 calling conventions. The BSD function is the same as POSIX.1 `setpgid'
654 (above). The System V function takes no arguments and puts the calling
655 process in its on group like `setpgid (0, 0)'.
656
657 New programs should always use `setpgid' instead.
658
659 GNU provides the POSIX.1 function. */
660
661/* Set the process group ID of the calling process to its own PID.
662 This is exactly the same as `setpgid (0, 0)'. */
663extern int setpgrp (void) __THROW;
664
665#endif /* Use misc or X/Open. */
666
667/* Create a new session with the calling process as its leader.
668 The process group IDs of the session and the calling process
669 are set to the process ID of the calling process, which is returned. */
670extern __pid_t setsid (void) __THROW;
671
672#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
673/* Return the session ID of the given process. */
674extern __pid_t getsid (__pid_t __pid) __THROW;
675#endif
676
677/* Get the real user ID of the calling process. */
678extern __uid_t getuid (void) __THROW;
679
680/* Get the effective user ID of the calling process. */
681extern __uid_t geteuid (void) __THROW;
682
683/* Get the real group ID of the calling process. */
684extern __gid_t getgid (void) __THROW;
685
686/* Get the effective group ID of the calling process. */
687extern __gid_t getegid (void) __THROW;
688
689/* If SIZE is zero, return the number of supplementary groups
690 the calling process is in. Otherwise, fill in the group IDs
691 of its supplementary groups in LIST and return the number written. */
692extern int getgroups (int __size, __gid_t __list[]) __THROW __wur;
693
694#ifdef __USE_GNU
695/* Return nonzero iff the calling process is in group GID. */
696extern int group_member (__gid_t __gid) __THROW;
697#endif
698
699/* Set the user ID of the calling process to UID.
700 If the calling process is the super-user, set the real
701 and effective user IDs, and the saved set-user-ID to UID;
702 if not, the effective user ID is set to UID. */
703extern int setuid (__uid_t __uid) __THROW __wur;
704
705#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
706/* Set the real user ID of the calling process to RUID,
707 and the effective user ID of the calling process to EUID. */
708extern int setreuid (__uid_t __ruid, __uid_t __euid) __THROW __wur;
709#endif
710
711#ifdef __USE_XOPEN2K
712/* Set the effective user ID of the calling process to UID. */
713extern int seteuid (__uid_t __uid) __THROW __wur;
714#endif /* Use POSIX.1-2001. */
715
716/* Set the group ID of the calling process to GID.
717 If the calling process is the super-user, set the real
718 and effective group IDs, and the saved set-group-ID to GID;
719 if not, the effective group ID is set to GID. */
720extern int setgid (__gid_t __gid) __THROW __wur;
721
722#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
723/* Set the real group ID of the calling process to RGID,
724 and the effective group ID of the calling process to EGID. */
725extern int setregid (__gid_t __rgid, __gid_t __egid) __THROW __wur;
726#endif
727
728#ifdef __USE_XOPEN2K
729/* Set the effective group ID of the calling process to GID. */
730extern int setegid (__gid_t __gid) __THROW __wur;
731#endif /* Use POSIX.1-2001. */
732
733#ifdef __USE_GNU
734/* Fetch the real user ID, effective user ID, and saved-set user ID,
735 of the calling process. */
736extern int getresuid (__uid_t *__ruid, __uid_t *__euid, __uid_t *__suid)
737 __THROW;
738
739/* Fetch the real group ID, effective group ID, and saved-set group ID,
740 of the calling process. */
741extern int getresgid (__gid_t *__rgid, __gid_t *__egid, __gid_t *__sgid)
742 __THROW;
743
744/* Set the real user ID, effective user ID, and saved-set user ID,
745 of the calling process to RUID, EUID, and SUID, respectively. */
746extern int setresuid (__uid_t __ruid, __uid_t __euid, __uid_t __suid)
747 __THROW __wur;
748
749/* Set the real group ID, effective group ID, and saved-set group ID,
750 of the calling process to RGID, EGID, and SGID, respectively. */
751extern int setresgid (__gid_t __rgid, __gid_t __egid, __gid_t __sgid)
752 __THROW __wur;
753#endif
754
755
756/* Clone the calling process, creating an exact copy.
757 Return -1 for errors, 0 to the new process,
758 and the process ID of the new process to the old process. */
759extern __pid_t fork (void) __THROWNL;
760
761#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
762 || defined __USE_MISC
763/* Clone the calling process, but without copying the whole address space.
764 The calling process is suspended until the new process exits or is
765 replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
766 and the process ID of the new process to the old process. */
767extern __pid_t vfork (void) __THROW;
768#endif /* Use misc or XPG < 7. */
769
770
771/* Return the pathname of the terminal FD is open on, or NULL on errors.
772 The returned storage is good only until the next call to this function. */
773extern char *ttyname (int __fd) __THROW;
774
775/* Store at most BUFLEN characters of the pathname of the terminal FD is
776 open on in BUF. Return 0 on success, otherwise an error number. */
777extern int ttyname_r (int __fd, char *__buf, size_t __buflen)
778 __THROW __nonnull ((2)) __wur;
779
780/* Return 1 if FD is a valid descriptor associated
781 with a terminal, zero if not. */
782extern int isatty (int __fd) __THROW;
783
784#ifdef __USE_MISC
785/* Return the index into the active-logins file (utmp) for
786 the controlling terminal. */
787extern int ttyslot (void) __THROW;
788#endif
789
790
791/* Make a link to FROM named TO. */
792extern int link (const char *__from, const char *__to)
793 __THROW __nonnull ((1, 2)) __wur;
794
795#ifdef __USE_ATFILE
796/* Like link but relative paths in TO and FROM are interpreted relative
797 to FROMFD and TOFD respectively. */
798extern int linkat (int __fromfd, const char *__from, int __tofd,
799 const char *__to, int __flags)
800 __THROW __nonnull ((2, 4)) __wur;
801#endif
802
803#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
804/* Make a symbolic link to FROM named TO. */
805extern int symlink (const char *__from, const char *__to)
806 __THROW __nonnull ((1, 2)) __wur;
807
808/* Read the contents of the symbolic link PATH into no more than
809 LEN bytes of BUF. The contents are not null-terminated.
810 Returns the number of characters read, or -1 for errors. */
811extern ssize_t readlink (const char *__restrict __path,
812 char *__restrict __buf, size_t __len)
813 __THROW __nonnull ((1, 2)) __wur;
814#endif /* Use POSIX.1-2001. */
815
816#ifdef __USE_ATFILE
817/* Like symlink but a relative path in TO is interpreted relative to TOFD. */
818extern int symlinkat (const char *__from, int __tofd,
819 const char *__to) __THROW __nonnull ((1, 3)) __wur;
820
821/* Like readlink but a relative PATH is interpreted relative to FD. */
822extern ssize_t readlinkat (int __fd, const char *__restrict __path,
823 char *__restrict __buf, size_t __len)
824 __THROW __nonnull ((2, 3)) __wur;
825#endif
826
827/* Remove the link NAME. */
828extern int unlink (const char *__name) __THROW __nonnull ((1));
829
830#ifdef __USE_ATFILE
831/* Remove the link NAME relative to FD. */
832extern int unlinkat (int __fd, const char *__name, int __flag)
833 __THROW __nonnull ((2));
834#endif
835
836/* Remove the directory PATH. */
837extern int rmdir (const char *__path) __THROW __nonnull ((1));
838
839
840/* Return the foreground process group ID of FD. */
841extern __pid_t tcgetpgrp (int __fd) __THROW;
842
843/* Set the foreground process group ID of FD set PGRP_ID. */
844extern int tcsetpgrp (int __fd, __pid_t __pgrp_id) __THROW;
845
846
847/* Return the login name of the user.
848
849 This function is a possible cancellation point and therefore not
850 marked with __THROW. */
851extern char *getlogin (void);
852#ifdef __USE_POSIX199506
853/* Return at most NAME_LEN characters of the login name of the user in NAME.
854 If it cannot be determined or some other error occurred, return the error
855 code. Otherwise return 0.
856
857 This function is a possible cancellation point and therefore not
858 marked with __THROW. */
859extern int getlogin_r (char *__name, size_t __name_len) __nonnull ((1));
860#endif
861
862#ifdef __USE_MISC
863/* Set the login name returned by `getlogin'. */
864extern int setlogin (const char *__name) __THROW __nonnull ((1));
865#endif
866
867
868#ifdef __USE_POSIX2
869/* Get definitions and prototypes for functions to process the
870 arguments in ARGV (ARGC of them, minus the program name) for
871 options given in OPTS. */
872# include <bits/getopt_posix.h>
873#endif
874
875
876#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
877/* Put the name of the current host in no more than LEN bytes of NAME.
878 The result is null-terminated if LEN is large enough for the full
879 name and the terminator. */
880extern int gethostname (char *__name, size_t __len) __THROW __nonnull ((1));
881#endif
882
883
884#if defined __USE_MISC
885/* Set the name of the current host to NAME, which is LEN bytes long.
886 This call is restricted to the super-user. */
887extern int sethostname (const char *__name, size_t __len)
888 __THROW __nonnull ((1)) __wur;
889
890/* Set the current machine's Internet number to ID.
891 This call is restricted to the super-user. */
892extern int sethostid (long int __id) __THROW __wur;
893
894
895/* Get and set the NIS (aka YP) domain name, if any.
896 Called just like `gethostname' and `sethostname'.
897 The NIS domain name is usually the empty string when not using NIS. */
898extern int getdomainname (char *__name, size_t __len)
899 __THROW __nonnull ((1)) __wur;
900extern int setdomainname (const char *__name, size_t __len)
901 __THROW __nonnull ((1)) __wur;
902
903
904/* Revoke access permissions to all processes currently communicating
905 with the control terminal, and then send a SIGHUP signal to the process
906 group of the control terminal. */
907extern int vhangup (void) __THROW;
908
909/* Revoke the access of all descriptors currently open on FILE. */
910extern int revoke (const char *__file) __THROW __nonnull ((1)) __wur;
911
912
913/* Enable statistical profiling, writing samples of the PC into at most
914 SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
915 is enabled, the system examines the user PC and increments
916 SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536]. If SCALE is zero,
917 disable profiling. Returns zero on success, -1 on error. */
918extern int profil (unsigned short int *__sample_buffer, size_t __size,
919 size_t __offset, unsigned int __scale)
920 __THROW __nonnull ((1));
921
922
923/* Turn accounting on if NAME is an existing file. The system will then write
924 a record for each process as it terminates, to this file. If NAME is NULL,
925 turn accounting off. This call is restricted to the super-user. */
926extern int acct (const char *__name) __THROW;
927
928
929/* Successive calls return the shells listed in `/etc/shells'. */
930extern char *getusershell (void) __THROW;
931extern void endusershell (void) __THROW; /* Discard cached info. */
932extern void setusershell (void) __THROW; /* Rewind and re-read the file. */
933
934
935/* Put the program in the background, and dissociate from the controlling
936 terminal. If NOCHDIR is zero, do `chdir ("/")'. If NOCLOSE is zero,
937 redirects stdin, stdout, and stderr to /dev/null. */
938extern int daemon (int __nochdir, int __noclose) __THROW __wur;
939#endif /* Use misc. */
940
941
942#if defined __USE_MISC || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
943/* Make PATH be the root directory (the starting point for absolute paths).
944 This call is restricted to the super-user. */
945extern int chroot (const char *__path) __THROW __nonnull ((1)) __wur;
946
947/* Prompt with PROMPT and read a string from the terminal without echoing.
948 Uses /dev/tty if possible; otherwise stderr and stdin. */
949extern char *getpass (const char *__prompt) __nonnull ((1));
950#endif /* Use misc || X/Open. */
951
952
953/* Make all changes done to FD actually appear on disk.
954
955 This function is a cancellation point and therefore not marked with
956 __THROW. */
957extern int fsync (int __fd);
958
959
960#ifdef __USE_GNU
961/* Make all changes done to all files on the file system associated
962 with FD actually appear on disk. */
963extern int syncfs (int __fd) __THROW;
964#endif
965
966
967#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
968
969/* Return identifier for the current host. */
970extern long int gethostid (void);
971
972/* Make all changes done to all files actually appear on disk. */
973extern void sync (void) __THROW;
974
975
976# if defined __USE_MISC || !defined __USE_XOPEN2K
977/* Return the number of bytes in a page. This is the system's page size,
978 which is not necessarily the same as the hardware page size. */
979extern int getpagesize (void) __THROW __attribute__ ((__const__));
980
981
982/* Return the maximum number of file descriptors
983 the current process could possibly have. */
984extern int getdtablesize (void) __THROW;
985# endif
986
987#endif /* Use misc || X/Open Unix. */
988
989
990#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
991
992/* Truncate FILE to LENGTH bytes. */
993# ifndef __USE_FILE_OFFSET64
994extern int truncate (const char *__file, __off_t __length)
995 __THROW __nonnull ((1)) __wur;
996# else
997# ifdef __REDIRECT_NTH
998extern int __REDIRECT_NTH (truncate,
999 (const char *__file, __off64_t __length),
1000 truncate64) __nonnull ((1)) __wur;
1001# else
1002# define truncate truncate64
1003# endif
1004# endif
1005# ifdef __USE_LARGEFILE64
1006extern int truncate64 (const char *__file, __off64_t __length)
1007 __THROW __nonnull ((1)) __wur;
1008# endif
1009
1010#endif /* Use X/Open Unix || POSIX 2008. */
1011
1012#if defined __USE_POSIX199309 \
1013 || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
1014
1015/* Truncate the file FD is open on to LENGTH bytes. */
1016# ifndef __USE_FILE_OFFSET64
1017extern int ftruncate (int __fd, __off_t __length) __THROW __wur;
1018# else
1019# ifdef __REDIRECT_NTH
1020extern int __REDIRECT_NTH (ftruncate, (int __fd, __off64_t __length),
1021 ftruncate64) __wur;
1022# else
1023# define ftruncate ftruncate64
1024# endif
1025# endif
1026# ifdef __USE_LARGEFILE64
1027extern int ftruncate64 (int __fd, __off64_t __length) __THROW __wur;
1028# endif
1029
1030#endif /* Use POSIX.1b || X/Open Unix || XPG6. */
1031
1032
1033#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K) \
1034 || defined __USE_MISC
1035
1036/* Set the end of accessible data space (aka "the break") to ADDR.
1037 Returns zero on success and -1 for errors (with errno set). */
1038extern int brk (void *__addr) __THROW __wur;
1039
1040/* Increase or decrease the end of accessible data space by DELTA bytes.
1041 If successful, returns the address the previous end of data space
1042 (i.e. the beginning of the new space, if DELTA > 0);
1043 returns (void *) -1 for errors (with errno set). */
1044extern void *sbrk (intptr_t __delta) __THROW;
1045#endif
1046
1047
1048#ifdef __USE_MISC
1049/* Invoke `system call' number SYSNO, passing it the remaining arguments.
1050 This is completely system-dependent, and not often useful.
1051
1052 In Unix, `syscall' sets `errno' for all errors and most calls return -1
1053 for errors; in many systems you cannot pass arguments or get return
1054 values for all system calls (`pipe', `fork', and `getppid' typically
1055 among them).
1056
1057 In Mach, all system calls take normal arguments and always return an
1058 error code (zero for success). */
1059extern long int syscall (long int __sysno, ...) __THROW;
1060
1061#endif /* Use misc. */
1062
1063
1064#if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
1065/* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
1066 files consistent. Some systems have them there and some here, and some
1067 software depends on the macros being defined without including both. */
1068
1069/* `lockf' is a simpler interface to the locking facilities of `fcntl'.
1070 LEN is always relative to the current file position.
1071 The CMD argument is one of the following.
1072
1073 This function is a cancellation point and therefore not marked with
1074 __THROW. */
1075
1076# define F_ULOCK 0 /* Unlock a previously locked region. */
1077# define F_LOCK 1 /* Lock a region for exclusive use. */
1078# define F_TLOCK 2 /* Test and lock a region for exclusive use. */
1079# define F_TEST 3 /* Test a region for other processes locks. */
1080
1081# ifndef __USE_FILE_OFFSET64
1082extern int lockf (int __fd, int __cmd, __off_t __len) __wur;
1083# else
1084# ifdef __REDIRECT
1085extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len),
1086 lockf64) __wur;
1087# else
1088# define lockf lockf64
1089# endif
1090# endif
1091# ifdef __USE_LARGEFILE64
1092extern int lockf64 (int __fd, int __cmd, __off64_t __len) __wur;
1093# endif
1094#endif /* Use misc and F_LOCK not already defined. */
1095
1096
1097#ifdef __USE_GNU
1098
1099/* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
1100 set to EINTR. */
1101
1102# define TEMP_FAILURE_RETRY(expression) \
1103 (__extension__ \
1104 ({ long int __result; \
1105 do __result = (long int) (expression); \
1106 while (__result == -1L && errno == EINTR); \
1107 __result; }))
1108
1109/* Copy LENGTH bytes from INFD to OUTFD. */
1110ssize_t copy_file_range (int __infd, __off64_t *__pinoff,
1111 int __outfd, __off64_t *__poutoff,
1112 size_t __length, unsigned int __flags);
1113#endif /* __USE_GNU */
1114
1115#if defined __USE_POSIX199309 || defined __USE_UNIX98
1116/* Synchronize at least the data part of a file with the underlying
1117 media. */
1118extern int fdatasync (int __fildes);
1119#endif /* Use POSIX199309 */
1120
1121
1122/* XPG4.2 specifies that prototypes for the encryption functions must
1123 be defined here. */
1124#ifdef __USE_XOPEN
1125/* Encrypt at most 8 characters from KEY using salt to perturb DES. */
1126extern char *crypt (const char *__key, const char *__salt)
1127 __THROW __nonnull ((1, 2));
1128
1129/* Encrypt data in BLOCK in place if EDFLAG is zero; otherwise decrypt
1130 block in place. */
1131extern void encrypt (char *__glibc_block, int __edflag)
1132 __THROW __nonnull ((1));
1133
1134
1135/* Swab pairs bytes in the first N bytes of the area pointed to by
1136 FROM and copy the result to TO. The value of TO must not be in the
1137 range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
1138 is without partner. */
1139extern void swab (const void *__restrict __from, void *__restrict __to,
1140 ssize_t __n) __THROW __nonnull ((1, 2));
1141#endif
1142
1143
1144/* Prior to Issue 6, the Single Unix Specification required these
1145 prototypes to appear in this header. They are also found in
1146 <stdio.h>. */
1147#if defined __USE_XOPEN && !defined __USE_XOPEN2K
1148/* Return the name of the controlling terminal. */
1149extern char *ctermid (char *__s) __THROW;
1150
1151/* Return the name of the current user. */
1152extern char *cuserid (char *__s);
1153#endif
1154
1155
1156/* Unix98 requires this function to be declared here. In other
1157 standards it is in <pthread.h>. */
1158#if defined __USE_UNIX98 && !defined __USE_XOPEN2K
1159extern int pthread_atfork (void (*__prepare) (void),
1160 void (*__parent) (void),
1161 void (*__child) (void)) __THROW;
1162#endif
1163
1164#ifdef __USE_MISC
1165/* Write LENGTH bytes of randomness starting at BUFFER. Return 0 on
1166 success or -1 on error. */
1167int getentropy (void *__buffer, size_t __length) __wur;
1168#endif
1169
1170/* Define some macros helping to catch buffer overflows. */
1171#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
1172# include <bits/unistd.h>
1173#endif
1174
1175__END_DECLS
1176
1177#endif /* unistd.h */
1178