(__sched_cpucount): Allow using special instruction for counting bits.
[glibc.git] / posix / unistd.h
bloba86968a8db606e1c1fe41a0059930bd99e10c88b
1 /* Copyright (C) 1991-2006, 2007 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
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.
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.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, write to the Free
16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17 02111-1307 USA. */
20 * POSIX Standard: 2.10 Symbolic Constants <unistd.h>
23 #ifndef _UNISTD_H
24 #define _UNISTD_H 1
26 #include <features.h>
28 __BEGIN_DECLS
30 /* These may be used to determine what facilities are present at compile time.
31 Their values can be obtained at run time from `sysconf'. */
33 /* POSIX Standard approved as ISO/IEC 9945-1 as of December 2001. */
34 #define _POSIX_VERSION 200112L
36 /* These are not #ifdef __USE_POSIX2 because they are
37 in the theoretically application-owned namespace. */
39 /* The utilities on GNU systems also correspond to this version. */
40 #define _POSIX2_VERSION 200112L
42 /* If defined, the implementation supports the
43 C Language Bindings Option. */
44 #define _POSIX2_C_BIND 200112L
46 /* If defined, the implementation supports the
47 C Language Development Utilities Option. */
48 #define _POSIX2_C_DEV 200112L
50 /* If defined, the implementation supports the
51 Software Development Utilities Option. */
52 #define _POSIX2_SW_DEV 200112L
54 /* If defined, the implementation supports the
55 creation of locales with the localedef utility. */
56 #define _POSIX2_LOCALEDEF 200112L
58 /* X/Open version number to which the library conforms. It is selectable. */
59 #ifdef __USE_XOPEN2K
60 # define _XOPEN_VERSION 600
61 #elif defined __USE_UNIX98
62 # define _XOPEN_VERSION 500
63 #else
64 # define _XOPEN_VERSION 4
65 #endif
67 /* Commands and utilities from XPG4 are available. */
68 #define _XOPEN_XCU_VERSION 4
70 /* We are compatible with the old published standards as well. */
71 #define _XOPEN_XPG2 1
72 #define _XOPEN_XPG3 1
73 #define _XOPEN_XPG4 1
75 /* The X/Open Unix extensions are available. */
76 #define _XOPEN_UNIX 1
78 /* Encryption is present. */
79 #define _XOPEN_CRYPT 1
81 /* The enhanced internationalization capabilities according to XPG4.2
82 are present. */
83 #define _XOPEN_ENH_I18N 1
85 /* The legacy interfaces are also available. */
86 #define _XOPEN_LEGACY 1
89 /* Get values of POSIX options:
91 If these symbols are defined, the corresponding features are
92 always available. If not, they may be available sometimes.
93 The current values can be obtained with `sysconf'.
95 _POSIX_JOB_CONTROL Job control is supported.
96 _POSIX_SAVED_IDS Processes have a saved set-user-ID
97 and a saved set-group-ID.
98 _POSIX_REALTIME_SIGNALS Real-time, queued signals are supported.
99 _POSIX_PRIORITY_SCHEDULING Priority scheduling is supported.
100 _POSIX_TIMERS POSIX.4 clocks and timers are supported.
101 _POSIX_ASYNCHRONOUS_IO Asynchronous I/O is supported.
102 _POSIX_PRIORITIZED_IO Prioritized asynchronous I/O is supported.
103 _POSIX_SYNCHRONIZED_IO Synchronizing file data is supported.
104 _POSIX_FSYNC The fsync function is present.
105 _POSIX_MAPPED_FILES Mapping of files to memory is supported.
106 _POSIX_MEMLOCK Locking of all memory is supported.
107 _POSIX_MEMLOCK_RANGE Locking of ranges of memory is supported.
108 _POSIX_MEMORY_PROTECTION Setting of memory protections is supported.
109 _POSIX_MESSAGE_PASSING POSIX.4 message queues are supported.
110 _POSIX_SEMAPHORES POSIX.4 counting semaphores are supported.
111 _POSIX_SHARED_MEMORY_OBJECTS POSIX.4 shared memory objects are supported.
112 _POSIX_THREADS POSIX.1c pthreads are supported.
113 _POSIX_THREAD_ATTR_STACKADDR Thread stack address attribute option supported.
114 _POSIX_THREAD_ATTR_STACKSIZE Thread stack size attribute option supported.
115 _POSIX_THREAD_SAFE_FUNCTIONS Thread-safe functions are supported.
116 _POSIX_THREAD_PRIORITY_SCHEDULING
117 POSIX.1c thread execution scheduling supported.
118 _POSIX_THREAD_PRIO_INHERIT Thread priority inheritance option supported.
119 _POSIX_THREAD_PRIO_PROTECT Thread priority protection option supported.
120 _POSIX_THREAD_PROCESS_SHARED Process-shared synchronization supported.
121 _POSIX_PII Protocol-independent interfaces are supported.
122 _POSIX_PII_XTI XTI protocol-indep. interfaces are supported.
123 _POSIX_PII_SOCKET Socket protocol-indep. interfaces are supported.
124 _POSIX_PII_INTERNET Internet family of protocols supported.
125 _POSIX_PII_INTERNET_STREAM Connection-mode Internet protocol supported.
126 _POSIX_PII_INTERNET_DGRAM Connectionless Internet protocol supported.
127 _POSIX_PII_OSI ISO/OSI family of protocols supported.
128 _POSIX_PII_OSI_COTS Connection-mode ISO/OSI service supported.
129 _POSIX_PII_OSI_CLTS Connectionless ISO/OSI service supported.
130 _POSIX_POLL Implementation supports `poll' function.
131 _POSIX_SELECT Implementation supports `select' and `pselect'.
133 _XOPEN_REALTIME X/Open realtime support is available.
134 _XOPEN_REALTIME_THREADS X/Open realtime thread support is available.
135 _XOPEN_SHM Shared memory interface according to XPG4.2.
137 _XBS5_ILP32_OFF32 Implementation provides environment with 32-bit
138 int, long, pointer, and off_t types.
139 _XBS5_ILP32_OFFBIG Implementation provides environment with 32-bit
140 int, long, and pointer and off_t with at least
141 64 bits.
142 _XBS5_LP64_OFF64 Implementation provides environment with 32-bit
143 int, and 64-bit long, pointer, and off_t types.
144 _XBS5_LPBIG_OFFBIG Implementation provides environment with at
145 least 32 bits int and long, pointer, and off_t
146 with at least 64 bits.
148 If any of these symbols is defined as -1, the corresponding option is not
149 true for any file. If any is defined as other than -1, the corresponding
150 option is true for all files. If a symbol is not defined at all, the value
151 for a specific file can be obtained from `pathconf' and `fpathconf'.
153 _POSIX_CHOWN_RESTRICTED Only the super user can use `chown' to change
154 the owner of a file. `chown' can only be used
155 to change the group ID of a file to a group of
156 which the calling process is a member.
157 _POSIX_NO_TRUNC Pathname components longer than
158 NAME_MAX generate an error.
159 _POSIX_VDISABLE If defined, if the value of an element of the
160 `c_cc' member of `struct termios' is
161 _POSIX_VDISABLE, no character will have the
162 effect associated with that element.
163 _POSIX_SYNC_IO Synchronous I/O may be performed.
164 _POSIX_ASYNC_IO Asynchronous I/O may be performed.
165 _POSIX_PRIO_IO Prioritized Asynchronous I/O may be performed.
167 Support for the Large File Support interface is not generally available.
168 If it is available the following constants are defined to one.
169 _LFS64_LARGEFILE Low-level I/O supports large files.
170 _LFS64_STDIO Standard I/O supports large files.
173 #include <bits/posix_opt.h>
175 /* Get the environment definitions from Unix98. */
176 #ifdef __USE_UNIX98
177 # include <bits/environments.h>
178 #endif
180 /* Standard file descriptors. */
181 #define STDIN_FILENO 0 /* Standard input. */
182 #define STDOUT_FILENO 1 /* Standard output. */
183 #define STDERR_FILENO 2 /* Standard error output. */
186 /* All functions that are not declared anywhere else. */
188 #include <bits/types.h>
190 #ifndef __ssize_t_defined
191 typedef __ssize_t ssize_t;
192 # define __ssize_t_defined
193 #endif
195 #define __need_size_t
196 #define __need_NULL
197 #include <stddef.h>
199 #if defined __USE_XOPEN || defined __USE_XOPEN2K
200 /* The Single Unix specification says that some more types are
201 available here. */
202 # ifndef __gid_t_defined
203 typedef __gid_t gid_t;
204 # define __gid_t_defined
205 # endif
207 # ifndef __uid_t_defined
208 typedef __uid_t uid_t;
209 # define __uid_t_defined
210 # endif
212 # ifndef __off_t_defined
213 # ifndef __USE_FILE_OFFSET64
214 typedef __off_t off_t;
215 # else
216 typedef __off64_t off_t;
217 # endif
218 # define __off_t_defined
219 # endif
220 # if defined __USE_LARGEFILE64 && !defined __off64_t_defined
221 typedef __off64_t off64_t;
222 # define __off64_t_defined
223 # endif
225 # ifndef __useconds_t_defined
226 typedef __useconds_t useconds_t;
227 # define __useconds_t_defined
228 # endif
230 # ifndef __pid_t_defined
231 typedef __pid_t pid_t;
232 # define __pid_t_defined
233 # endif
234 #endif /* X/Open */
236 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
237 # ifndef __intptr_t_defined
238 typedef __intptr_t intptr_t;
239 # define __intptr_t_defined
240 # endif
241 #endif
243 #if defined __USE_BSD || defined __USE_XOPEN
244 # ifndef __socklen_t_defined
245 typedef __socklen_t socklen_t;
246 # define __socklen_t_defined
247 # endif
248 #endif
250 /* Values for the second argument to access.
251 These may be OR'd together. */
252 #define R_OK 4 /* Test for read permission. */
253 #define W_OK 2 /* Test for write permission. */
254 #define X_OK 1 /* Test for execute permission. */
255 #define F_OK 0 /* Test for existence. */
257 /* Test for access to NAME using the real UID and real GID. */
258 extern int access (__const char *__name, int __type) __THROW __nonnull ((1));
260 #ifdef __USE_GNU
261 /* Test for access to NAME using the effective UID and GID
262 (as normal file operations use). */
263 extern int euidaccess (__const char *__name, int __type)
264 __THROW __nonnull ((1));
266 /* An alias for `euidaccess', used by some other systems. */
267 extern int eaccess (__const char *__name, int __type)
268 __THROW __nonnull ((1));
269 #endif
271 #ifdef __USE_ATFILE
272 /* Test for access to FILE relative to the directory FD is open on.
273 If AT_EACCESS is set in FLAG, then use effective IDs like `eaccess',
274 otherwise use real IDs like `access'. */
275 extern int faccessat (int __fd, __const char *__file, int __type, int __flag)
276 __THROW __nonnull ((2)) __wur;
277 #endif /* Use GNU. */
280 /* Values for the WHENCE argument to lseek. */
281 #ifndef _STDIO_H /* <stdio.h> has the same definitions. */
282 # define SEEK_SET 0 /* Seek from beginning of file. */
283 # define SEEK_CUR 1 /* Seek from current position. */
284 # define SEEK_END 2 /* Seek from end of file. */
285 #endif
287 #if defined __USE_BSD && !defined L_SET
288 /* Old BSD names for the same constants; just for compatibility. */
289 # define L_SET SEEK_SET
290 # define L_INCR SEEK_CUR
291 # define L_XTND SEEK_END
292 #endif
295 /* Move FD's file position to OFFSET bytes from the
296 beginning of the file (if WHENCE is SEEK_SET),
297 the current position (if WHENCE is SEEK_CUR),
298 or the end of the file (if WHENCE is SEEK_END).
299 Return the new file position. */
300 #ifndef __USE_FILE_OFFSET64
301 extern __off_t lseek (int __fd, __off_t __offset, int __whence) __THROW;
302 #else
303 # ifdef __REDIRECT_NTH
304 extern __off64_t __REDIRECT_NTH (lseek,
305 (int __fd, __off64_t __offset, int __whence),
306 lseek64);
307 # else
308 # define lseek lseek64
309 # endif
310 #endif
311 #ifdef __USE_LARGEFILE64
312 extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence)
313 __THROW;
314 #endif
316 /* Close the file descriptor FD.
318 This function is a cancellation point and therefore not marked with
319 __THROW. */
320 extern int close (int __fd);
322 /* Read NBYTES into BUF from FD. Return the
323 number read, -1 for errors or 0 for EOF.
325 This function is a cancellation point and therefore not marked with
326 __THROW. */
327 extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __wur;
329 /* Write N bytes of BUF to FD. Return the number written, or -1.
331 This function is a cancellation point and therefore not marked with
332 __THROW. */
333 extern ssize_t write (int __fd, __const void *__buf, size_t __n) __wur;
335 #ifdef __USE_UNIX98
336 # ifndef __USE_FILE_OFFSET64
337 /* Read NBYTES into BUF from FD at the given position OFFSET without
338 changing the file pointer. Return the number read, -1 for errors
339 or 0 for EOF.
341 This function is a cancellation point and therefore not marked with
342 __THROW. */
343 extern ssize_t pread (int __fd, void *__buf, size_t __nbytes,
344 __off_t __offset) __wur;
346 /* Write N bytes of BUF to FD at the given position OFFSET without
347 changing the file pointer. Return the number written, or -1.
349 This function is a cancellation point and therefore not marked with
350 __THROW. */
351 extern ssize_t pwrite (int __fd, __const void *__buf, size_t __n,
352 __off_t __offset) __wur;
353 # else
354 # ifdef __REDIRECT
355 extern ssize_t __REDIRECT (pread, (int __fd, void *__buf, size_t __nbytes,
356 __off64_t __offset),
357 pread64) __wur;
358 extern ssize_t __REDIRECT (pwrite, (int __fd, __const void *__buf,
359 size_t __nbytes, __off64_t __offset),
360 pwrite64) __wur;
361 # else
362 # define pread pread64
363 # define pwrite pwrite64
364 # endif
365 # endif
367 # ifdef __USE_LARGEFILE64
368 /* Read NBYTES into BUF from FD at the given position OFFSET without
369 changing the file pointer. Return the number read, -1 for errors
370 or 0 for EOF. */
371 extern ssize_t pread64 (int __fd, void *__buf, size_t __nbytes,
372 __off64_t __offset) __wur;
373 /* Write N bytes of BUF to FD at the given position OFFSET without
374 changing the file pointer. Return the number written, or -1. */
375 extern ssize_t pwrite64 (int __fd, __const void *__buf, size_t __n,
376 __off64_t __offset) __wur;
377 # endif
378 #endif
380 /* Create a one-way communication channel (pipe).
381 If successful, two file descriptors are stored in PIPEDES;
382 bytes written on PIPEDES[1] can be read from PIPEDES[0].
383 Returns 0 if successful, -1 if not. */
384 extern int pipe (int __pipedes[2]) __THROW __wur;
386 /* Schedule an alarm. In SECONDS seconds, the process will get a SIGALRM.
387 If SECONDS is zero, any currently scheduled alarm will be cancelled.
388 The function returns the number of seconds remaining until the last
389 alarm scheduled would have signaled, or zero if there wasn't one.
390 There is no return value to indicate an error, but you can set `errno'
391 to 0 and check its value after calling `alarm', and this might tell you.
392 The signal may come late due to processor scheduling. */
393 extern unsigned int alarm (unsigned int __seconds) __THROW;
395 /* Make the process sleep for SECONDS seconds, or until a signal arrives
396 and is not ignored. The function returns the number of seconds less
397 than SECONDS which it actually slept (thus zero if it slept the full time).
398 If a signal handler does a `longjmp' or modifies the handling of the
399 SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
400 signal afterwards is undefined. There is no return value to indicate
401 error, but if `sleep' returns SECONDS, it probably didn't work.
403 This function is a cancellation point and therefore not marked with
404 __THROW. */
405 extern unsigned int sleep (unsigned int __seconds);
407 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
408 /* Set an alarm to go off (generating a SIGALRM signal) in VALUE
409 microseconds. If INTERVAL is nonzero, when the alarm goes off, the
410 timer is reset to go off every INTERVAL microseconds thereafter.
411 Returns the number of microseconds remaining before the alarm. */
412 extern __useconds_t ualarm (__useconds_t __value, __useconds_t __interval)
413 __THROW;
415 /* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
416 or ignored.
418 This function is a cancellation point and therefore not marked with
419 __THROW. */
420 extern int usleep (__useconds_t __useconds);
421 #endif
424 /* Suspend the process until a signal arrives.
425 This always returns -1 and sets `errno' to EINTR.
427 This function is a cancellation point and therefore not marked with
428 __THROW. */
429 extern int pause (void);
432 /* Change the owner and group of FILE. */
433 extern int chown (__const char *__file, __uid_t __owner, __gid_t __group)
434 __THROW __nonnull ((1)) __wur;
436 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
437 /* Change the owner and group of the file that FD is open on. */
438 extern int fchown (int __fd, __uid_t __owner, __gid_t __group) __THROW __wur;
441 /* Change owner and group of FILE, if it is a symbolic
442 link the ownership of the symbolic link is changed. */
443 extern int lchown (__const char *__file, __uid_t __owner, __gid_t __group)
444 __THROW __nonnull ((1)) __wur;
446 #endif /* Use BSD || X/Open Unix. */
448 #ifdef __USE_ATFILE
449 /* Change the owner and group of FILE relative to the directory FD is open
450 on. */
451 extern int fchownat (int __fd, __const char *__file, __uid_t __owner,
452 __gid_t __group, int __flag)
453 __THROW __nonnull ((2)) __wur;
454 #endif /* Use GNU. */
456 /* Change the process's working directory to PATH. */
457 extern int chdir (__const char *__path) __THROW __nonnull ((1)) __wur;
459 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
460 /* Change the process's working directory to the one FD is open on. */
461 extern int fchdir (int __fd) __THROW __wur;
462 #endif
464 /* Get the pathname of the current working directory,
465 and put it in SIZE bytes of BUF. Returns NULL if the
466 directory couldn't be determined or SIZE was too small.
467 If successful, returns BUF. In GNU, if BUF is NULL,
468 an array is allocated with `malloc'; the array is SIZE
469 bytes long, unless SIZE == 0, in which case it is as
470 big as necessary. */
471 extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
473 #ifdef __USE_GNU
474 /* Return a malloc'd string containing the current directory name.
475 If the environment variable `PWD' is set, and its value is correct,
476 that value is used. */
477 extern char *get_current_dir_name (void) __THROW;
478 #endif
480 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
481 /* Put the absolute pathname of the current working directory in BUF.
482 If successful, return BUF. If not, put an error message in
483 BUF and return NULL. BUF should be at least PATH_MAX bytes long. */
484 extern char *getwd (char *__buf)
485 __THROW __nonnull ((1)) __attribute_deprecated__ __wur;
486 #endif
489 /* Duplicate FD, returning a new file descriptor on the same file. */
490 extern int dup (int __fd) __THROW __wur;
492 /* Duplicate FD to FD2, closing FD2 and making it open on the same file. */
493 extern int dup2 (int __fd, int __fd2) __THROW;
495 /* NULL-terminated array of "NAME=VALUE" environment variables. */
496 extern char **__environ;
497 #ifdef __USE_GNU
498 extern char **environ;
499 #endif
502 /* Replace the current process, executing PATH with arguments ARGV and
503 environment ENVP. ARGV and ENVP are terminated by NULL pointers. */
504 extern int execve (__const char *__path, char *__const __argv[],
505 char *__const __envp[]) __THROW __nonnull ((1));
507 #ifdef __USE_GNU
508 /* Execute the file FD refers to, overlaying the running program image.
509 ARGV and ENVP are passed to the new program, as for `execve'. */
510 extern int fexecve (int __fd, char *__const __argv[], char *__const __envp[])
511 __THROW;
512 #endif
515 /* Execute PATH with arguments ARGV and environment from `environ'. */
516 extern int execv (__const char *__path, char *__const __argv[])
517 __THROW __nonnull ((1));
519 /* Execute PATH with all arguments after PATH until a NULL pointer,
520 and the argument after that for environment. */
521 extern int execle (__const char *__path, __const char *__arg, ...)
522 __THROW __nonnull ((1));
524 /* Execute PATH with all arguments after PATH until
525 a NULL pointer and environment from `environ'. */
526 extern int execl (__const char *__path, __const char *__arg, ...)
527 __THROW __nonnull ((1));
529 /* Execute FILE, searching in the `PATH' environment variable if it contains
530 no slashes, with arguments ARGV and environment from `environ'. */
531 extern int execvp (__const char *__file, char *__const __argv[])
532 __THROW __nonnull ((1));
534 /* Execute FILE, searching in the `PATH' environment variable if
535 it contains no slashes, with all arguments after FILE until a
536 NULL pointer and environment from `environ'. */
537 extern int execlp (__const char *__file, __const char *__arg, ...)
538 __THROW __nonnull ((1));
541 #if defined __USE_MISC || defined __USE_XOPEN
542 /* Add INC to priority of the current process. */
543 extern int nice (int __inc) __THROW __wur;
544 #endif
547 /* Terminate program execution with the low-order 8 bits of STATUS. */
548 extern void _exit (int __status) __attribute__ ((__noreturn__));
551 /* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
552 the `_SC_*' symbols for the NAME argument to `sysconf';
553 and the `_CS_*' symbols for the NAME argument to `confstr'. */
554 #include <bits/confname.h>
556 /* Get file-specific configuration information about PATH. */
557 extern long int pathconf (__const char *__path, int __name)
558 __THROW __nonnull ((1));
560 /* Get file-specific configuration about descriptor FD. */
561 extern long int fpathconf (int __fd, int __name) __THROW;
563 /* Get the value of the system variable NAME. */
564 extern long int sysconf (int __name) __THROW;
566 #ifdef __USE_POSIX2
567 /* Get the value of the string-valued system variable NAME. */
568 extern size_t confstr (int __name, char *__buf, size_t __len) __THROW;
569 #endif
572 /* Get the process ID of the calling process. */
573 extern __pid_t getpid (void) __THROW;
575 /* Get the process ID of the calling process's parent. */
576 extern __pid_t getppid (void) __THROW;
578 /* Get the process group ID of the calling process.
579 This function is different on old BSD. */
580 #ifndef __FAVOR_BSD
581 extern __pid_t getpgrp (void) __THROW;
582 #else
583 # ifdef __REDIRECT_NTH
584 extern __pid_t __REDIRECT_NTH (getpgrp, (__pid_t __pid), __getpgid);
585 # else
586 # define getpgrp __getpgid
587 # endif
588 #endif
590 /* Get the process group ID of process PID. */
591 extern __pid_t __getpgid (__pid_t __pid) __THROW;
592 #ifdef __USE_XOPEN_EXTENDED
593 extern __pid_t getpgid (__pid_t __pid) __THROW;
594 #endif
597 /* Set the process group ID of the process matching PID to PGID.
598 If PID is zero, the current process's process group ID is set.
599 If PGID is zero, the process ID of the process is used. */
600 extern int setpgid (__pid_t __pid, __pid_t __pgid) __THROW;
602 #if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED
603 /* Both System V and BSD have `setpgrp' functions, but with different
604 calling conventions. The BSD function is the same as POSIX.1 `setpgid'
605 (above). The System V function takes no arguments and puts the calling
606 process in its on group like `setpgid (0, 0)'.
608 New programs should always use `setpgid' instead.
610 The default in GNU is to provide the System V function. The BSD
611 function is available under -D_BSD_SOURCE. */
613 # ifndef __FAVOR_BSD
615 /* Set the process group ID of the calling process to its own PID.
616 This is exactly the same as `setpgid (0, 0)'. */
617 extern int setpgrp (void) __THROW;
619 # else
621 /* Another name for `setpgid' (above). */
622 # ifdef __REDIRECT_NTH
623 extern int __REDIRECT_NTH (setpgrp, (__pid_t __pid, __pid_t __pgrp), setpgid);
624 # else
625 # define setpgrp setpgid
626 # endif
628 # endif /* Favor BSD. */
629 #endif /* Use SVID or BSD. */
631 /* Create a new session with the calling process as its leader.
632 The process group IDs of the session and the calling process
633 are set to the process ID of the calling process, which is returned. */
634 extern __pid_t setsid (void) __THROW;
636 #ifdef __USE_XOPEN_EXTENDED
637 /* Return the session ID of the given process. */
638 extern __pid_t getsid (__pid_t __pid) __THROW;
639 #endif
641 /* Get the real user ID of the calling process. */
642 extern __uid_t getuid (void) __THROW;
644 /* Get the effective user ID of the calling process. */
645 extern __uid_t geteuid (void) __THROW;
647 /* Get the real group ID of the calling process. */
648 extern __gid_t getgid (void) __THROW;
650 /* Get the effective group ID of the calling process. */
651 extern __gid_t getegid (void) __THROW;
653 /* If SIZE is zero, return the number of supplementary groups
654 the calling process is in. Otherwise, fill in the group IDs
655 of its supplementary groups in LIST and return the number written. */
656 extern int getgroups (int __size, __gid_t __list[]) __THROW __wur;
658 #ifdef __USE_GNU
659 /* Return nonzero iff the calling process is in group GID. */
660 extern int group_member (__gid_t __gid) __THROW;
661 #endif
663 /* Set the user ID of the calling process to UID.
664 If the calling process is the super-user, set the real
665 and effective user IDs, and the saved set-user-ID to UID;
666 if not, the effective user ID is set to UID. */
667 extern int setuid (__uid_t __uid) __THROW;
669 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
670 /* Set the real user ID of the calling process to RUID,
671 and the effective user ID of the calling process to EUID. */
672 extern int setreuid (__uid_t __ruid, __uid_t __euid) __THROW;
673 #endif
675 #if defined __USE_BSD || defined __USE_XOPEN2K
676 /* Set the effective user ID of the calling process to UID. */
677 extern int seteuid (__uid_t __uid) __THROW;
678 #endif /* Use BSD. */
680 /* Set the group ID of the calling process to GID.
681 If the calling process is the super-user, set the real
682 and effective group IDs, and the saved set-group-ID to GID;
683 if not, the effective group ID is set to GID. */
684 extern int setgid (__gid_t __gid) __THROW;
686 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
687 /* Set the real group ID of the calling process to RGID,
688 and the effective group ID of the calling process to EGID. */
689 extern int setregid (__gid_t __rgid, __gid_t __egid) __THROW;
690 #endif
692 #if defined __USE_BSD || defined __USE_XOPEN2K
693 /* Set the effective group ID of the calling process to GID. */
694 extern int setegid (__gid_t __gid) __THROW;
695 #endif /* Use BSD. */
697 #ifdef __USE_GNU
698 /* Fetch the real user ID, effective user ID, and saved-set user ID,
699 of the calling process. */
700 extern int getresuid (__uid_t *__ruid, __uid_t *__euid, __uid_t *__suid)
701 __THROW;
703 /* Fetch the real group ID, effective group ID, and saved-set group ID,
704 of the calling process. */
705 extern int getresgid (__gid_t *__rgid, __gid_t *__egid, __gid_t *__sgid)
706 __THROW;
708 /* Set the real user ID, effective user ID, and saved-set user ID,
709 of the calling process to RUID, EUID, and SUID, respectively. */
710 extern int setresuid (__uid_t __ruid, __uid_t __euid, __uid_t __suid)
711 __THROW;
713 /* Set the real group ID, effective group ID, and saved-set group ID,
714 of the calling process to RGID, EGID, and SGID, respectively. */
715 extern int setresgid (__gid_t __rgid, __gid_t __egid, __gid_t __sgid)
716 __THROW;
717 #endif
720 /* Clone the calling process, creating an exact copy.
721 Return -1 for errors, 0 to the new process,
722 and the process ID of the new process to the old process. */
723 extern __pid_t fork (void) __THROW;
725 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
726 /* Clone the calling process, but without copying the whole address space.
727 The calling process is suspended until the new process exits or is
728 replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
729 and the process ID of the new process to the old process. */
730 extern __pid_t vfork (void) __THROW;
731 #endif /* Use BSD. */
734 /* Return the pathname of the terminal FD is open on, or NULL on errors.
735 The returned storage is good only until the next call to this function. */
736 extern char *ttyname (int __fd) __THROW;
738 /* Store at most BUFLEN characters of the pathname of the terminal FD is
739 open on in BUF. Return 0 on success, otherwise an error number. */
740 extern int ttyname_r (int __fd, char *__buf, size_t __buflen)
741 __THROW __nonnull ((2)) __wur;
743 /* Return 1 if FD is a valid descriptor associated
744 with a terminal, zero if not. */
745 extern int isatty (int __fd) __THROW;
747 #if defined __USE_BSD \
748 || (defined __USE_XOPEN_EXTENDED && !defined __USE_UNIX98)
749 /* Return the index into the active-logins file (utmp) for
750 the controlling terminal. */
751 extern int ttyslot (void) __THROW;
752 #endif
755 /* Make a link to FROM named TO. */
756 extern int link (__const char *__from, __const char *__to)
757 __THROW __nonnull ((1, 2)) __wur;
759 #ifdef __USE_ATFILE
760 /* Like link but relative paths in TO and FROM are interpreted relative
761 to FROMFD and TOFD respectively. */
762 extern int linkat (int __fromfd, __const char *__from, int __tofd,
763 __const char *__to, int __flags)
764 __THROW __nonnull ((2, 4)) __wur;
765 #endif
767 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
768 /* Make a symbolic link to FROM named TO. */
769 extern int symlink (__const char *__from, __const char *__to)
770 __THROW __nonnull ((1, 2)) __wur;
772 /* Read the contents of the symbolic link PATH into no more than
773 LEN bytes of BUF. The contents are not null-terminated.
774 Returns the number of characters read, or -1 for errors. */
775 extern ssize_t readlink (__const char *__restrict __path,
776 char *__restrict __buf, size_t __len)
777 __THROW __nonnull ((1, 2)) __wur;
778 #endif /* Use BSD. */
780 #ifdef __USE_ATFILE
781 /* Like symlink but a relative path in TO is interpreted relative to TOFD. */
782 extern int symlinkat (__const char *__from, int __tofd,
783 __const char *__to) __THROW __nonnull ((1, 3)) __wur;
785 /* Like readlink but a relative PATH is interpreted relative to FD. */
786 extern ssize_t readlinkat (int __fd, __const char *__restrict __path,
787 char *__restrict __buf, size_t __len)
788 __THROW __nonnull ((2, 3)) __wur;
789 #endif
791 /* Remove the link NAME. */
792 extern int unlink (__const char *__name) __THROW __nonnull ((1));
794 #ifdef __USE_ATFILE
795 /* Remove the link NAME relative to FD. */
796 extern int unlinkat (int __fd, __const char *__name, int __flag)
797 __THROW __nonnull ((2));
798 #endif
800 /* Remove the directory PATH. */
801 extern int rmdir (__const char *__path) __THROW __nonnull ((1));
804 /* Return the foreground process group ID of FD. */
805 extern __pid_t tcgetpgrp (int __fd) __THROW;
807 /* Set the foreground process group ID of FD set PGRP_ID. */
808 extern int tcsetpgrp (int __fd, __pid_t __pgrp_id) __THROW;
811 /* Return the login name of the user.
813 This function is a possible cancellation points and therefore not
814 marked with __THROW. */
815 extern char *getlogin (void);
816 #if defined __USE_REENTRANT || defined __USE_POSIX199506
817 /* Return at most NAME_LEN characters of the login name of the user in NAME.
818 If it cannot be determined or some other error occurred, return the error
819 code. Otherwise return 0.
821 This function is a possible cancellation points and therefore not
822 marked with __THROW. */
823 extern int getlogin_r (char *__name, size_t __name_len) __nonnull ((1));
824 #endif
826 #ifdef __USE_BSD
827 /* Set the login name returned by `getlogin'. */
828 extern int setlogin (__const char *__name) __THROW __nonnull ((1));
829 #endif
832 #ifdef __USE_POSIX2
833 /* Get definitions and prototypes for functions to process the
834 arguments in ARGV (ARGC of them, minus the program name) for
835 options given in OPTS. */
836 # define __need_getopt
837 # include <getopt.h>
838 #endif
841 #if defined __USE_BSD || defined __USE_UNIX98
842 /* Put the name of the current host in no more than LEN bytes of NAME.
843 The result is null-terminated if LEN is large enough for the full
844 name and the terminator. */
845 extern int gethostname (char *__name, size_t __len) __THROW __nonnull ((1));
846 #endif
849 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_UNIX98)
850 /* Set the name of the current host to NAME, which is LEN bytes long.
851 This call is restricted to the super-user. */
852 extern int sethostname (__const char *__name, size_t __len)
853 __THROW __nonnull ((1)) __wur;
855 /* Set the current machine's Internet number to ID.
856 This call is restricted to the super-user. */
857 extern int sethostid (long int __id) __THROW __wur;
860 /* Get and set the NIS (aka YP) domain name, if any.
861 Called just like `gethostname' and `sethostname'.
862 The NIS domain name is usually the empty string when not using NIS. */
863 extern int getdomainname (char *__name, size_t __len)
864 __THROW __nonnull ((1)) __wur;
865 extern int setdomainname (__const char *__name, size_t __len)
866 __THROW __nonnull ((1)) __wur;
869 /* Revoke access permissions to all processes currently communicating
870 with the control terminal, and then send a SIGHUP signal to the process
871 group of the control terminal. */
872 extern int vhangup (void) __THROW;
874 /* Revoke the access of all descriptors currently open on FILE. */
875 extern int revoke (__const char *__file) __THROW __nonnull ((1)) __wur;
878 /* Enable statistical profiling, writing samples of the PC into at most
879 SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
880 is enabled, the system examines the user PC and increments
881 SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536]. If SCALE is zero,
882 disable profiling. Returns zero on success, -1 on error. */
883 extern int profil (unsigned short int *__sample_buffer, size_t __size,
884 size_t __offset, unsigned int __scale)
885 __THROW __nonnull ((1));
888 /* Turn accounting on if NAME is an existing file. The system will then write
889 a record for each process as it terminates, to this file. If NAME is NULL,
890 turn accounting off. This call is restricted to the super-user. */
891 extern int acct (__const char *__name) __THROW;
894 /* Successive calls return the shells listed in `/etc/shells'. */
895 extern char *getusershell (void) __THROW;
896 extern void endusershell (void) __THROW; /* Discard cached info. */
897 extern void setusershell (void) __THROW; /* Rewind and re-read the file. */
900 /* Put the program in the background, and dissociate from the controlling
901 terminal. If NOCHDIR is zero, do `chdir ("/")'. If NOCLOSE is zero,
902 redirects stdin, stdout, and stderr to /dev/null. */
903 extern int daemon (int __nochdir, int __noclose) __THROW __wur;
904 #endif /* Use BSD || X/Open. */
907 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
908 /* Make PATH be the root directory (the starting point for absolute paths).
909 This call is restricted to the super-user. */
910 extern int chroot (__const char *__path) __THROW __nonnull ((1)) __wur;
912 /* Prompt with PROMPT and read a string from the terminal without echoing.
913 Uses /dev/tty if possible; otherwise stderr and stdin. */
914 extern char *getpass (__const char *__prompt) __nonnull ((1));
915 #endif /* Use BSD || X/Open. */
918 #if defined __USE_BSD || defined __USE_XOPEN
919 /* Make all changes done to FD actually appear on disk.
921 This function is a cancellation point and therefore not marked with
922 __THROW. */
923 extern int fsync (int __fd);
924 #endif /* Use BSD || X/Open. */
927 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
929 /* Return identifier for the current host. */
930 extern long int gethostid (void);
932 /* Make all changes done to all files actually appear on disk. */
933 extern void sync (void) __THROW;
936 /* Return the number of bytes in a page. This is the system's page size,
937 which is not necessarily the same as the hardware page size. */
938 extern int getpagesize (void) __THROW __attribute__ ((__const__));
941 /* Return the maximum number of file descriptors
942 the current process could possibly have. */
943 extern int getdtablesize (void) __THROW;
946 /* Truncate FILE to LENGTH bytes. */
947 # ifndef __USE_FILE_OFFSET64
948 extern int truncate (__const char *__file, __off_t __length)
949 __THROW __nonnull ((1)) __wur;
950 # else
951 # ifdef __REDIRECT_NTH
952 extern int __REDIRECT_NTH (truncate,
953 (__const char *__file, __off64_t __length),
954 truncate64) __nonnull ((1)) __wur;
955 # else
956 # define truncate truncate64
957 # endif
958 # endif
959 # ifdef __USE_LARGEFILE64
960 extern int truncate64 (__const char *__file, __off64_t __length)
961 __THROW __nonnull ((1)) __wur;
962 # endif
964 #endif /* Use BSD || X/Open Unix. */
966 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
968 /* Truncate the file FD is open on to LENGTH bytes. */
969 # ifndef __USE_FILE_OFFSET64
970 extern int ftruncate (int __fd, __off_t __length) __THROW __wur;
971 # else
972 # ifdef __REDIRECT_NTH
973 extern int __REDIRECT_NTH (ftruncate, (int __fd, __off64_t __length),
974 ftruncate64) __wur;
975 # else
976 # define ftruncate ftruncate64
977 # endif
978 # endif
979 # ifdef __USE_LARGEFILE64
980 extern int ftruncate64 (int __fd, __off64_t __length) __THROW __wur;
981 # endif
983 #endif /* Use BSD || X/Open Unix || POSIX 2003. */
986 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
988 /* Set the end of accessible data space (aka "the break") to ADDR.
989 Returns zero on success and -1 for errors (with errno set). */
990 extern int brk (void *__addr) __THROW __wur;
992 /* Increase or decrease the end of accessible data space by DELTA bytes.
993 If successful, returns the address the previous end of data space
994 (i.e. the beginning of the new space, if DELTA > 0);
995 returns (void *) -1 for errors (with errno set). */
996 extern void *sbrk (intptr_t __delta) __THROW;
997 #endif
1000 #ifdef __USE_MISC
1001 /* Invoke `system call' number SYSNO, passing it the remaining arguments.
1002 This is completely system-dependent, and not often useful.
1004 In Unix, `syscall' sets `errno' for all errors and most calls return -1
1005 for errors; in many systems you cannot pass arguments or get return
1006 values for all system calls (`pipe', `fork', and `getppid' typically
1007 among them).
1009 In Mach, all system calls take normal arguments and always return an
1010 error code (zero for success). */
1011 extern long int syscall (long int __sysno, ...) __THROW;
1013 #endif /* Use misc. */
1016 #if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
1017 /* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
1018 files consistent. Some systems have them there and some here, and some
1019 software depends on the macros being defined without including both. */
1021 /* `lockf' is a simpler interface to the locking facilities of `fcntl'.
1022 LEN is always relative to the current file position.
1023 The CMD argument is one of the following.
1025 This function is a cancellation point and therefore not marked with
1026 __THROW. */
1028 # define F_ULOCK 0 /* Unlock a previously locked region. */
1029 # define F_LOCK 1 /* Lock a region for exclusive use. */
1030 # define F_TLOCK 2 /* Test and lock a region for exclusive use. */
1031 # define F_TEST 3 /* Test a region for other processes locks. */
1033 # ifndef __USE_FILE_OFFSET64
1034 extern int lockf (int __fd, int __cmd, __off_t __len) __wur;
1035 # else
1036 # ifdef __REDIRECT
1037 extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len),
1038 lockf64) __wur;
1039 # else
1040 # define lockf lockf64
1041 # endif
1042 # endif
1043 # ifdef __USE_LARGEFILE64
1044 extern int lockf64 (int __fd, int __cmd, __off64_t __len) __wur;
1045 # endif
1046 #endif /* Use misc and F_LOCK not already defined. */
1049 #ifdef __USE_GNU
1051 /* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
1052 set to EINTR. */
1054 # define TEMP_FAILURE_RETRY(expression) \
1055 (__extension__ \
1056 ({ long int __result; \
1057 do __result = (long int) (expression); \
1058 while (__result == -1L && errno == EINTR); \
1059 __result; }))
1060 #endif
1062 #if defined __USE_POSIX199309 || defined __USE_UNIX98
1063 /* Synchronize at least the data part of a file with the underlying
1064 media. */
1065 extern int fdatasync (int __fildes);
1066 #endif /* Use POSIX199309 */
1069 /* XPG4.2 specifies that prototypes for the encryption functions must
1070 be defined here. */
1071 #ifdef __USE_XOPEN
1072 /* Encrypt at most 8 characters from KEY using salt to perturb DES. */
1073 extern char *crypt (__const char *__key, __const char *__salt)
1074 __THROW __nonnull ((1, 2));
1076 /* Encrypt data in BLOCK in place if EDFLAG is zero; otherwise decrypt
1077 block in place. */
1078 extern void encrypt (char *__block, int __edflag) __THROW __nonnull ((1));
1081 /* Swab pairs bytes in the first N bytes of the area pointed to by
1082 FROM and copy the result to TO. The value of TO must not be in the
1083 range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
1084 is without partner. */
1085 extern void swab (__const void *__restrict __from, void *__restrict __to,
1086 ssize_t __n) __THROW __nonnull ((1, 2));
1087 #endif
1090 /* The Single Unix specification demands this prototype to be here.
1091 It is also found in <stdio.h>. */
1092 #ifdef __USE_XOPEN
1093 /* Return the name of the controlling terminal. */
1094 extern char *ctermid (char *__s) __THROW;
1095 #endif
1098 /* Define some macros helping to catch buffer overflows. */
1099 #if __USE_FORTIFY_LEVEL > 0 && !defined __cplusplus
1100 # include <bits/unistd.h>
1101 #endif
1103 __END_DECLS
1105 #endif /* unistd.h */