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#include <sys/sysmacros.h>
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
334
335#define llseek lseek
336#define ustat statfs
337#ifndef __USE_FILE_OFFSET64
338extern __off_t lseek (int __fd, __off_t __offset, int __whence) __THROW;
339#else
340# ifdef __REDIRECT_NTH
341extern __off64_t __REDIRECT_NTH (lseek,
342 (int __fd, __off64_t __offset, int __whence),
343 lseek64);
344# else
345# define lseek lseek64
346# endif
347#endif
348#ifdef __USE_LARGEFILE64
349extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence)
350 __THROW;
351#endif
352
353/* Close the file descriptor FD.
354
355 This function is a cancellation point and therefore not marked with
356 __THROW. */
357extern int close (int __fd);
358
359/* Read NBYTES into BUF from FD. Return the
360 number read, -1 for errors or 0 for EOF.
361
362 This function is a cancellation point and therefore not marked with
363 __THROW. */
364extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __wur;
365
366/* Write N bytes of BUF to FD. Return the number written, or -1.
367
368 This function is a cancellation point and therefore not marked with
369 __THROW. */
370extern ssize_t write (int __fd, const void *__buf, size_t __n) __wur;
371
372#if defined __USE_UNIX98 || defined __USE_XOPEN2K8
373# ifndef __USE_FILE_OFFSET64
374/* Read NBYTES into BUF from FD at the given position OFFSET without
375 changing the file pointer. Return the number read, -1 for errors
376 or 0 for EOF.
377
378 This function is a cancellation point and therefore not marked with
379 __THROW. */
380extern ssize_t pread (int __fd, void *__buf, size_t __nbytes,
381 __off_t __offset) __wur;
382
383/* Write N bytes of BUF to FD at the given position OFFSET without
384 changing the file pointer. Return the number written, or -1.
385
386 This function is a cancellation point and therefore not marked with
387 __THROW. */
388extern ssize_t pwrite (int __fd, const void *__buf, size_t __n,
389 __off_t __offset) __wur;
390# else
391# ifdef __REDIRECT
392extern ssize_t __REDIRECT (pread, (int __fd, void *__buf, size_t __nbytes,
393 __off64_t __offset),
394 pread64) __wur;
395extern ssize_t __REDIRECT (pwrite, (int __fd, const void *__buf,
396 size_t __nbytes, __off64_t __offset),
397 pwrite64) __wur;
398# else
399# define pread pread64
400# define pwrite pwrite64
401# endif
402# endif
403
404# ifdef __USE_LARGEFILE64
405/* Read NBYTES into BUF from FD at the given position OFFSET without
406 changing the file pointer. Return the number read, -1 for errors
407 or 0 for EOF. */
408extern ssize_t pread64 (int __fd, void *__buf, size_t __nbytes,
409 __off64_t __offset) __wur;
410/* Write N bytes of BUF to FD at the given position OFFSET without
411 changing the file pointer. Return the number written, or -1. */
412extern ssize_t pwrite64 (int __fd, const void *__buf, size_t __n,
413 __off64_t __offset) __wur;
414# endif
415#endif
416
417/* Create a one-way communication channel (pipe).
418 If successful, two file descriptors are stored in PIPEDES;
419 bytes written on PIPEDES[1] can be read from PIPEDES[0].
420 Returns 0 if successful, -1 if not. */
421extern int pipe (int __pipedes[2]) __THROW __wur;
422
423#ifdef __USE_GNU
424/* Same as pipe but apply flags passed in FLAGS to the new file
425 descriptors. */
426extern int pipe2 (int __pipedes[2], int __flags) __THROW __wur;
427#endif
428
429/* Schedule an alarm. In SECONDS seconds, the process will get a SIGALRM.
430 If SECONDS is zero, any currently scheduled alarm will be cancelled.
431 The function returns the number of seconds remaining until the last
432 alarm scheduled would have signaled, or zero if there wasn't one.
433 There is no return value to indicate an error, but you can set `errno'
434 to 0 and check its value after calling `alarm', and this might tell you.
435 The signal may come late due to processor scheduling. */
436extern unsigned int alarm (unsigned int __seconds) __THROW;
437
438/* Make the process sleep for SECONDS seconds, or until a signal arrives
439 and is not ignored. The function returns the number of seconds less
440 than SECONDS which it actually slept (thus zero if it slept the full time).
441 If a signal handler does a `longjmp' or modifies the handling of the
442 SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
443 signal afterwards is undefined. There is no return value to indicate
444 error, but if `sleep' returns SECONDS, it probably didn't work.
445
446 This function is a cancellation point and therefore not marked with
447 __THROW. */
448extern unsigned int sleep (unsigned int __seconds);
449
450#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
451 || defined __USE_MISC
452/* Set an alarm to go off (generating a SIGALRM signal) in VALUE
453 microseconds. If INTERVAL is nonzero, when the alarm goes off, the
454 timer is reset to go off every INTERVAL microseconds thereafter.
455 Returns the number of microseconds remaining before the alarm. */
456extern __useconds_t ualarm (__useconds_t __value, __useconds_t __interval)
457 __THROW;
458
459/* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
460 or ignored.
461
462 This function is a cancellation point and therefore not marked with
463 __THROW. */
464extern int usleep (__useconds_t __useconds);
465#endif
466
467
468/* Suspend the process until a signal arrives.
469 This always returns -1 and sets `errno' to EINTR.
470
471 This function is a cancellation point and therefore not marked with
472 __THROW. */
473extern int pause (void);
474
475
476/* Change the owner and group of FILE. */
477extern int chown (const char *__file, __uid_t __owner, __gid_t __group)
478 __THROW __nonnull ((1)) __wur;
479
480#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
481/* Change the owner and group of the file that FD is open on. */
482extern int fchown (int __fd, __uid_t __owner, __gid_t __group) __THROW __wur;
483
484
485/* Change owner and group of FILE, if it is a symbolic
486 link the ownership of the symbolic link is changed. */
487extern int lchown (const char *__file, __uid_t __owner, __gid_t __group)
488 __THROW __nonnull ((1)) __wur;
489
490#endif /* Use X/Open Unix. */
491
492#ifdef __USE_ATFILE
493/* Change the owner and group of FILE relative to the directory FD is open
494 on. */
495extern int fchownat (int __fd, const char *__file, __uid_t __owner,
496 __gid_t __group, int __flag)
497 __THROW __nonnull ((2)) __wur;
498#endif /* Use GNU. */
499
500/* Change the process's working directory to PATH. */
501extern int chdir (const char *__path) __THROW __nonnull ((1)) __wur;
502
503#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
504/* Change the process's working directory to the one FD is open on. */
505extern int fchdir (int __fd) __THROW __wur;
506#endif
507
508/* Get the pathname of the current working directory,
509 and put it in SIZE bytes of BUF. Returns NULL if the
510 directory couldn't be determined or SIZE was too small.
511 If successful, returns BUF. In GNU, if BUF is NULL,
512 an array is allocated with `malloc'; the array is SIZE
513 bytes long, unless SIZE == 0, in which case it is as
514 big as necessary. */
515extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
516
517#ifdef __USE_GNU
518/* Return a malloc'd string containing the current directory name.
519 If the environment variable `PWD' is set, and its value is correct,
520 that value is used. */
521extern char *get_current_dir_name (void) __THROW;
522#endif
523
524#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
525 || defined __USE_MISC
526/* Put the absolute pathname of the current working directory in BUF.
527 If successful, return BUF. If not, put an error message in
528 BUF and return NULL. BUF should be at least PATH_MAX bytes long. */
529extern char *getwd (char *__buf)
530 __THROW __nonnull ((1)) __attribute_deprecated__ __wur;
531#endif
532
533
534/* Duplicate FD, returning a new file descriptor on the same file. */
535extern int dup (int __fd) __THROW __wur;
536
537/* Duplicate FD to FD2, closing FD2 and making it open on the same file. */
538extern int dup2 (int __fd, int __fd2) __THROW;
539
540#ifdef __USE_GNU
541/* Duplicate FD to FD2, closing FD2 and making it open on the same
542 file while setting flags according to FLAGS. */
543extern int dup3 (int __fd, int __fd2, int __flags) __THROW;
544#endif
545
546/* NULL-terminated array of "NAME=VALUE" environment variables. */
547extern char **__environ;
548#ifdef __USE_GNU
549extern char **environ;
550#endif
551
552
553/* Replace the current process, executing PATH with arguments ARGV and
554 environment ENVP. ARGV and ENVP are terminated by NULL pointers. */
555extern int execve (const char *__path, char *const __argv[],
556 char *const __envp[]) __THROW __nonnull ((1, 2));
557
558#ifdef __USE_XOPEN2K8
559/* Execute the file FD refers to, overlaying the running program image.
560 ARGV and ENVP are passed to the new program, as for `execve'. */
561extern int fexecve (int __fd, char *const __argv[], char *const __envp[])
562 __THROW __nonnull ((2));
563#endif
564
565
566/* Execute PATH with arguments ARGV and environment from `environ'. */
567extern int execv (const char *__path, char *const __argv[])
568 __THROW __nonnull ((1, 2));
569
570/* Execute PATH with all arguments after PATH until a NULL pointer,
571 and the argument after that for environment. */
572extern int execle (const char *__path, const char *__arg, ...)
573 __THROW __nonnull ((1, 2));
574
575/* Execute PATH with all arguments after PATH until
576 a NULL pointer and environment from `environ'. */
577extern int execl (const char *__path, const char *__arg, ...)
578 __THROW __nonnull ((1, 2));
579
580/* Execute FILE, searching in the `PATH' environment variable if it contains
581 no slashes, with arguments ARGV and environment from `environ'. */
582extern int execvp (const char *__file, char *const __argv[])
583 __THROW __nonnull ((1, 2));
584
585/* Execute FILE, searching in the `PATH' environment variable if
586 it contains no slashes, with all arguments after FILE until a
587 NULL pointer and environment from `environ'. */
588extern int execlp (const char *__file, const char *__arg, ...)
589 __THROW __nonnull ((1, 2));
590
591#ifdef __USE_GNU
592/* Execute FILE, searching in the `PATH' environment variable if it contains
593 no slashes, with arguments ARGV and environment from `environ'. */
594extern int execvpe (const char *__file, char *const __argv[],
595 char *const __envp[])
596 __THROW __nonnull ((1, 2));
597#endif
598
599
600#if defined __USE_MISC || defined __USE_XOPEN
601/* Add INC to priority of the current process. */
602extern int nice (int __inc) __THROW __wur;
603#endif
604
605
606/* Terminate program execution with the low-order 8 bits of STATUS. */
607extern void _exit (int __status) __attribute__ ((__noreturn__));
608
609
610/* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
611 the `_SC_*' symbols for the NAME argument to `sysconf';
612 and the `_CS_*' symbols for the NAME argument to `confstr'. */
613#include <bits/confname.h>
614
615/* Get file-specific configuration information about PATH. */
616extern long int pathconf (const char *__path, int __name)
617 __THROW __nonnull ((1));
618
619/* Get file-specific configuration about descriptor FD. */
620extern long int fpathconf (int __fd, int __name) __THROW;
621
622/* Get the value of the system variable NAME. */
623extern long int sysconf (int __name) __THROW;
624
625#ifdef __USE_POSIX2
626/* Get the value of the string-valued system variable NAME. */
627extern size_t confstr (int __name, char *__buf, size_t __len) __THROW;
628#endif
629
630
631/* Get the process ID of the calling process. */
632extern __pid_t getpid (void) __THROW;
633
634/* Get the process ID of the calling process's parent. */
635extern __pid_t getppid (void) __THROW;
636
637/* Get the process group ID of the calling process. */
638extern __pid_t getpgrp (void) __THROW;
639
640/* Get the process group ID of process PID. */
641extern __pid_t __getpgid (__pid_t __pid) __THROW;
642#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
643extern __pid_t getpgid (__pid_t __pid) __THROW;
644#endif
645
646
647/* Set the process group ID of the process matching PID to PGID.
648 If PID is zero, the current process's process group ID is set.
649 If PGID is zero, the process ID of the process is used. */
650extern int setpgid (__pid_t __pid, __pid_t __pgid) __THROW;
651
652#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
653/* Both System V and BSD have `setpgrp' functions, but with different
654 calling conventions. The BSD function is the same as POSIX.1 `setpgid'
655 (above). The System V function takes no arguments and puts the calling
656 process in its on group like `setpgid (0, 0)'.
657
658 New programs should always use `setpgid' instead.
659
660 GNU provides the POSIX.1 function. */
661
662/* Set the process group ID of the calling process to its own PID.
663 This is exactly the same as `setpgid (0, 0)'. */
664extern int setpgrp (void) __THROW;
665
666#endif /* Use misc or X/Open. */
667
668/* Create a new session with the calling process as its leader.
669 The process group IDs of the session and the calling process
670 are set to the process ID of the calling process, which is returned. */
671extern __pid_t setsid (void) __THROW;
672
673#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
674/* Return the session ID of the given process. */
675extern __pid_t getsid (__pid_t __pid) __THROW;
676#endif
677
678/* Get the real user ID of the calling process. */
679extern __uid_t getuid (void) __THROW;
680
681/* Get the effective user ID of the calling process. */
682extern __uid_t geteuid (void) __THROW;
683
684/* Get the real group ID of the calling process. */
685extern __gid_t getgid (void) __THROW;
686
687/* Get the effective group ID of the calling process. */
688extern __gid_t getegid (void) __THROW;
689
690/* If SIZE is zero, return the number of supplementary groups
691 the calling process is in. Otherwise, fill in the group IDs
692 of its supplementary groups in LIST and return the number written. */
693extern int getgroups (int __size, __gid_t __list[]) __THROW __wur;
694
695#ifdef __USE_GNU
696/* Return nonzero iff the calling process is in group GID. */
697extern int group_member (__gid_t __gid) __THROW;
698#endif
699
700/* Set the user ID of the calling process to UID.
701 If the calling process is the super-user, set the real
702 and effective user IDs, and the saved set-user-ID to UID;
703 if not, the effective user ID is set to UID. */
704extern int setuid (__uid_t __uid) __THROW __wur;
705
706#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
707/* Set the real user ID of the calling process to RUID,
708 and the effective user ID of the calling process to EUID. */
709extern int setreuid (__uid_t __ruid, __uid_t __euid) __THROW __wur;
710#endif
711
712#ifdef __USE_XOPEN2K
713/* Set the effective user ID of the calling process to UID. */
714extern int seteuid (__uid_t __uid) __THROW __wur;
715#endif /* Use POSIX.1-2001. */
716
717/* Set the group ID of the calling process to GID.
718 If the calling process is the super-user, set the real
719 and effective group IDs, and the saved set-group-ID to GID;
720 if not, the effective group ID is set to GID. */
721extern int setgid (__gid_t __gid) __THROW __wur;
722
723#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
724/* Set the real group ID of the calling process to RGID,
725 and the effective group ID of the calling process to EGID. */
726extern int setregid (__gid_t __rgid, __gid_t __egid) __THROW __wur;
727#endif
728
729#ifdef __USE_XOPEN2K
730/* Set the effective group ID of the calling process to GID. */
731extern int setegid (__gid_t __gid) __THROW __wur;
732#endif /* Use POSIX.1-2001. */
733
734#ifdef __USE_GNU
735/* Fetch the real user ID, effective user ID, and saved-set user ID,
736 of the calling process. */
737extern int getresuid (__uid_t *__ruid, __uid_t *__euid, __uid_t *__suid)
738 __THROW;
739
740/* Fetch the real group ID, effective group ID, and saved-set group ID,
741 of the calling process. */
742extern int getresgid (__gid_t *__rgid, __gid_t *__egid, __gid_t *__sgid)
743 __THROW;
744
745/* Set the real user ID, effective user ID, and saved-set user ID,
746 of the calling process to RUID, EUID, and SUID, respectively. */
747extern int setresuid (__uid_t __ruid, __uid_t __euid, __uid_t __suid)
748 __THROW __wur;
749
750/* Set the real group ID, effective group ID, and saved-set group ID,
751 of the calling process to RGID, EGID, and SGID, respectively. */
752extern int setresgid (__gid_t __rgid, __gid_t __egid, __gid_t __sgid)
753 __THROW __wur;
754#endif
755
756
757/* Clone the calling process, creating an exact copy.
758 Return -1 for errors, 0 to the new process,
759 and the process ID of the new process to the old process. */
760extern __pid_t fork (void) __THROWNL;
761
762#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
763 || defined __USE_MISC
764/* Clone the calling process, but without copying the whole address space.
765 The calling process is suspended until the new process exits or is
766 replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
767 and the process ID of the new process to the old process. */
768extern __pid_t vfork (void) __THROW;
769#endif /* Use misc or XPG < 7. */
770
771
772/* Return the pathname of the terminal FD is open on, or NULL on errors.
773 The returned storage is good only until the next call to this function. */
774extern char *ttyname (int __fd) __THROW;
775
776/* Store at most BUFLEN characters of the pathname of the terminal FD is
777 open on in BUF. Return 0 on success, otherwise an error number. */
778extern int ttyname_r (int __fd, char *__buf, size_t __buflen)
779 __THROW __nonnull ((2)) __wur;
780
781/* Return 1 if FD is a valid descriptor associated
782 with a terminal, zero if not. */
783extern int isatty (int __fd) __THROW;
784
785#ifdef __USE_MISC
786/* Return the index into the active-logins file (utmp) for
787 the controlling terminal. */
788extern int ttyslot (void) __THROW;
789#endif
790
791
792/* Make a link to FROM named TO. */
793extern int link (const char *__from, const char *__to)
794 __THROW __nonnull ((1, 2)) __wur;
795
796#ifdef __USE_ATFILE
797/* Like link but relative paths in TO and FROM are interpreted relative
798 to FROMFD and TOFD respectively. */
799extern int linkat (int __fromfd, const char *__from, int __tofd,
800 const char *__to, int __flags)
801 __THROW __nonnull ((2, 4)) __wur;
802#endif
803
804#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
805/* Make a symbolic link to FROM named TO. */
806extern int symlink (const char *__from, const char *__to)
807 __THROW __nonnull ((1, 2)) __wur;
808
809/* Read the contents of the symbolic link PATH into no more than
810 LEN bytes of BUF. The contents are not null-terminated.
811 Returns the number of characters read, or -1 for errors. */
812extern ssize_t readlink (const char *__restrict __path,
813 char *__restrict __buf, size_t __len)
814 __THROW __nonnull ((1, 2)) __wur;
815#endif /* Use POSIX.1-2001. */
816
817#ifdef __USE_ATFILE
818/* Like symlink but a relative path in TO is interpreted relative to TOFD. */
819extern int symlinkat (const char *__from, int __tofd,
820 const char *__to) __THROW __nonnull ((1, 3)) __wur;
821
822/* Like readlink but a relative PATH is interpreted relative to FD. */
823extern ssize_t readlinkat (int __fd, const char *__restrict __path,
824 char *__restrict __buf, size_t __len)
825 __THROW __nonnull ((2, 3)) __wur;
826#endif
827
828/* Remove the link NAME. */
829extern int unlink (const char *__name) __THROW __nonnull ((1));
830
831#ifdef __USE_ATFILE
832/* Remove the link NAME relative to FD. */
833extern int unlinkat (int __fd, const char *__name, int __flag)
834 __THROW __nonnull ((2));
835#endif
836
837/* Remove the directory PATH. */
838extern int rmdir (const char *__path) __THROW __nonnull ((1));
839
840
841/* Return the foreground process group ID of FD. */
842extern __pid_t tcgetpgrp (int __fd) __THROW;
843
844/* Set the foreground process group ID of FD set PGRP_ID. */
845extern int tcsetpgrp (int __fd, __pid_t __pgrp_id) __THROW;
846
847
848/* Return the login name of the user.
849
850 This function is a possible cancellation point and therefore not
851 marked with __THROW. */
852extern char *getlogin (void);
853#ifdef __USE_POSIX199506
854/* Return at most NAME_LEN characters of the login name of the user in NAME.
855 If it cannot be determined or some other error occurred, return the error
856 code. Otherwise return 0.
857
858 This function is a possible cancellation point and therefore not
859 marked with __THROW. */
860extern int getlogin_r (char *__name, size_t __name_len) __nonnull ((1));
861#endif
862
863#ifdef __USE_MISC
864/* Set the login name returned by `getlogin'. */
865extern int setlogin (const char *__name) __THROW __nonnull ((1));
866#endif
867
868
869#ifdef __USE_POSIX2
870/* Get definitions and prototypes for functions to process the
871 arguments in ARGV (ARGC of them, minus the program name) for
872 options given in OPTS. */
873# include <bits/getopt_posix.h>
874#endif
875
876
877#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
878/* Put the name of the current host in no more than LEN bytes of NAME.
879 The result is null-terminated if LEN is large enough for the full
880 name and the terminator. */
881extern int gethostname (char *__name, size_t __len) __THROW __nonnull ((1));
882#endif
883
884
885#if defined __USE_MISC
886/* Set the name of the current host to NAME, which is LEN bytes long.
887 This call is restricted to the super-user. */
888extern int sethostname (const char *__name, size_t __len)
889 __THROW __nonnull ((1)) __wur;
890
891/* Set the current machine's Internet number to ID.
892 This call is restricted to the super-user. */
893extern int sethostid (long int __id) __THROW __wur;
894
895
896/* Get and set the NIS (aka YP) domain name, if any.
897 Called just like `gethostname' and `sethostname'.
898 The NIS domain name is usually the empty string when not using NIS. */
899extern int getdomainname (char *__name, size_t __len)
900 __THROW __nonnull ((1)) __wur;
901extern int setdomainname (const char *__name, size_t __len)
902 __THROW __nonnull ((1)) __wur;
903
904
905/* Revoke access permissions to all processes currently communicating
906 with the control terminal, and then send a SIGHUP signal to the process
907 group of the control terminal. */
908extern int vhangup (void) __THROW;
909
910/* Revoke the access of all descriptors currently open on FILE. */
911extern int revoke (const char *__file) __THROW __nonnull ((1)) __wur;
912
913
914/* Enable statistical profiling, writing samples of the PC into at most
915 SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
916 is enabled, the system examines the user PC and increments
917 SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536]. If SCALE is zero,
918 disable profiling. Returns zero on success, -1 on error. */
919extern int profil (unsigned short int *__sample_buffer, size_t __size,
920 size_t __offset, unsigned int __scale)
921 __THROW __nonnull ((1));
922
923
924/* Turn accounting on if NAME is an existing file. The system will then write
925 a record for each process as it terminates, to this file. If NAME is NULL,
926 turn accounting off. This call is restricted to the super-user. */
927extern int acct (const char *__name) __THROW;
928
929
930/* Successive calls return the shells listed in `/etc/shells'. */
931extern char *getusershell (void) __THROW;
932extern void endusershell (void) __THROW; /* Discard cached info. */
933extern void setusershell (void) __THROW; /* Rewind and re-read the file. */
934
935
936/* Put the program in the background, and dissociate from the controlling
937 terminal. If NOCHDIR is zero, do `chdir ("/")'. If NOCLOSE is zero,
938 redirects stdin, stdout, and stderr to /dev/null. */
939extern int daemon (int __nochdir, int __noclose) __THROW __wur;
940#endif /* Use misc. */
941
942
943#if defined __USE_MISC || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
944/* Make PATH be the root directory (the starting point for absolute paths).
945 This call is restricted to the super-user. */
946extern int chroot (const char *__path) __THROW __nonnull ((1)) __wur;
947
948/* Prompt with PROMPT and read a string from the terminal without echoing.
949 Uses /dev/tty if possible; otherwise stderr and stdin. */
950extern char *getpass (const char *__prompt) __nonnull ((1));
951#endif /* Use misc || X/Open. */
952
953
954/* Make all changes done to FD actually appear on disk.
955
956 This function is a cancellation point and therefore not marked with
957 __THROW. */
958extern int fsync (int __fd);
959
960
961#ifdef __USE_GNU
962/* Make all changes done to all files on the file system associated
963 with FD actually appear on disk. */
964extern int syncfs (int __fd) __THROW;
965#endif
966
967
968#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
969
970/* Return identifier for the current host. */
971extern long int gethostid (void);
972
973/* Make all changes done to all files actually appear on disk. */
974extern void sync (void) __THROW;
975
976
977# if defined __USE_MISC || !defined __USE_XOPEN2K
978/* Return the number of bytes in a page. This is the system's page size,
979 which is not necessarily the same as the hardware page size. */
980extern int getpagesize (void) __THROW __attribute__ ((__const__));
981
982
983/* Return the maximum number of file descriptors
984 the current process could possibly have. */
985extern int getdtablesize (void) __THROW;
986# endif
987
988#endif /* Use misc || X/Open Unix. */
989
990
991#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
992
993/* Truncate FILE to LENGTH bytes. */
994# ifndef __USE_FILE_OFFSET64
995extern int truncate (const char *__file, __off_t __length)
996 __THROW __nonnull ((1)) __wur;
997# else
998# ifdef __REDIRECT_NTH
999extern int __REDIRECT_NTH (truncate,
1000 (const char *__file, __off64_t __length),
1001 truncate64) __nonnull ((1)) __wur;
1002# else
1003# define truncate truncate64
1004# endif
1005# endif
1006# ifdef __USE_LARGEFILE64
1007extern int truncate64 (const char *__file, __off64_t __length)
1008 __THROW __nonnull ((1)) __wur;
1009# endif
1010
1011#endif /* Use X/Open Unix || POSIX 2008. */
1012
1013#if defined __USE_POSIX199309 \
1014 || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
1015
1016/* Truncate the file FD is open on to LENGTH bytes. */
1017# ifndef __USE_FILE_OFFSET64
1018extern int ftruncate (int __fd, __off_t __length) __THROW __wur;
1019# else
1020# ifdef __REDIRECT_NTH
1021extern int __REDIRECT_NTH (ftruncate, (int __fd, __off64_t __length),
1022 ftruncate64) __wur;
1023# else
1024# define ftruncate ftruncate64
1025# endif
1026# endif
1027# ifdef __USE_LARGEFILE64
1028extern int ftruncate64 (int __fd, __off64_t __length) __THROW __wur;
1029# endif
1030
1031#endif /* Use POSIX.1b || X/Open Unix || XPG6. */
1032
1033
1034#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K) \
1035 || defined __USE_MISC
1036
1037/* Set the end of accessible data space (aka "the break") to ADDR.
1038 Returns zero on success and -1 for errors (with errno set). */
1039extern int brk (void *__addr) __THROW __wur;
1040
1041/* Increase or decrease the end of accessible data space by DELTA bytes.
1042 If successful, returns the address the previous end of data space
1043 (i.e. the beginning of the new space, if DELTA > 0);
1044 returns (void *) -1 for errors (with errno set). */
1045extern void *sbrk (intptr_t __delta) __THROW;
1046#endif
1047
1048
1049#ifdef __USE_MISC
1050/* Invoke `system call' number SYSNO, passing it the remaining arguments.
1051 This is completely system-dependent, and not often useful.
1052
1053 In Unix, `syscall' sets `errno' for all errors and most calls return -1
1054 for errors; in many systems you cannot pass arguments or get return
1055 values for all system calls (`pipe', `fork', and `getppid' typically
1056 among them).
1057
1058 In Mach, all system calls take normal arguments and always return an
1059 error code (zero for success). */
1060extern long int syscall (long int __sysno, ...) __THROW;
1061
1062#endif /* Use misc. */
1063
1064
1065#if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
1066/* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
1067 files consistent. Some systems have them there and some here, and some
1068 software depends on the macros being defined without including both. */
1069
1070/* `lockf' is a simpler interface to the locking facilities of `fcntl'.
1071 LEN is always relative to the current file position.
1072 The CMD argument is one of the following.
1073
1074 This function is a cancellation point and therefore not marked with
1075 __THROW. */
1076
1077# define F_ULOCK 0 /* Unlock a previously locked region. */
1078# define F_LOCK 1 /* Lock a region for exclusive use. */
1079# define F_TLOCK 2 /* Test and lock a region for exclusive use. */
1080# define F_TEST 3 /* Test a region for other processes locks. */
1081
1082# ifndef __USE_FILE_OFFSET64
1083extern int lockf (int __fd, int __cmd, __off_t __len) __wur;
1084# else
1085# ifdef __REDIRECT
1086extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len),
1087 lockf64) __wur;
1088# else
1089# define lockf lockf64
1090# endif
1091# endif
1092# ifdef __USE_LARGEFILE64
1093extern int lockf64 (int __fd, int __cmd, __off64_t __len) __wur;
1094# endif
1095#endif /* Use misc and F_LOCK not already defined. */
1096
1097
1098#ifdef __USE_GNU
1099
1100/* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
1101 set to EINTR. */
1102
1103# define TEMP_FAILURE_RETRY(expression) \
1104 (__extension__ \
1105 ({ long int __result; \
1106 do __result = (long int) (expression); \
1107 while (__result == -1L && errno == EINTR); \
1108 __result; }))
1109
1110/* Copy LENGTH bytes from INFD to OUTFD. */
1111ssize_t copy_file_range (int __infd, __off64_t *__pinoff,
1112 int __outfd, __off64_t *__poutoff,
1113 size_t __length, unsigned int __flags);
1114#endif /* __USE_GNU */
1115
1116#if defined __USE_POSIX199309 || defined __USE_UNIX98
1117/* Synchronize at least the data part of a file with the underlying
1118 media. */
1119extern int fdatasync (int __fildes);
1120#endif /* Use POSIX199309 */
1121
1122#ifdef __USE_MISC
1123/* One-way hash PHRASE, returning a string suitable for storage in the
1124 user database. SALT selects the one-way function to use, and
1125 ensures that no two users' hashes are the same, even if they use
1126 the same passphrase. The return value points to static storage
1127 which will be overwritten by the next call to crypt. */
1128extern char *crypt (const char *__key, const char *__salt)
1129 __THROW __nonnull ((1, 2));
1130#endif
1131
1132#ifdef __USE_XOPEN
1133/* Swab pairs bytes in the first N bytes of the area pointed to by
1134 FROM and copy the result to TO. The value of TO must not be in the
1135 range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
1136 is without partner. */
1137extern void swab (const void *__restrict __from, void *__restrict __to,
1138 ssize_t __n) __THROW __nonnull ((1, 2));
1139#endif
1140
1141
1142/* Prior to Issue 6, the Single Unix Specification required these
1143 prototypes to appear in this header. They are also found in
1144 <stdio.h>. */
1145#if defined __USE_XOPEN && !defined __USE_XOPEN2K
1146/* Return the name of the controlling terminal. */
1147extern char *ctermid (char *__s) __THROW;
1148
1149/* Return the name of the current user. */
1150extern char *cuserid (char *__s);
1151#endif
1152
1153
1154/* Unix98 requires this function to be declared here. In other
1155 standards it is in <pthread.h>. */
1156#if defined __USE_UNIX98 && !defined __USE_XOPEN2K
1157extern int pthread_atfork (void (*__prepare) (void),
1158 void (*__parent) (void),
1159 void (*__child) (void)) __THROW;
1160#endif
1161
1162#ifdef __USE_MISC
1163/* Write LENGTH bytes of randomness starting at BUFFER. Return 0 on
1164 success or -1 on error. */
1165int getentropy (void *__buffer, size_t __length) __wur;
1166#endif
1167
1168/* Define some macros helping to catch buffer overflows. */
1169#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
1170# include <bits/unistd.h>
1171#endif
1172
1173__END_DECLS
1174
1175#endif /* unistd.h */
1176