1 /* Copyright (C) 1991-2009, 2010, 2011 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
20 * POSIX Standard: 2.10 Symbolic Constants <unistd.h>
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'. */
34 /* POSIX Standard approved as ISO/IEC 9945-1 as of September 2008. */
35 # define _POSIX_VERSION 200809L
36 #elif defined __USE_XOPEN2K
37 /* POSIX Standard approved as ISO/IEC 9945-1 as of December 2001. */
38 # define _POSIX_VERSION 200112L
39 #elif defined __USE_POSIX199506
40 /* POSIX Standard approved as ISO/IEC 9945-1 as of June 1995. */
41 # define _POSIX_VERSION 199506L
42 #elif defined __USE_POSIX199309
43 /* POSIX Standard approved as ISO/IEC 9945-1 as of September 1993. */
44 # define _POSIX_VERSION 199309L
46 /* POSIX Standard approved as ISO/IEC 9945-1 as of September 1990. */
47 # define _POSIX_VERSION 199009L
50 /* These are not #ifdef __USE_POSIX2 because they are
51 in the theoretically application-owned namespace. */
54 # define __POSIX2_THIS_VERSION 200809L
55 /* The utilities on GNU systems also correspond to this version. */
56 #elif defined __USE_XOPEN2K
57 /* The utilities on GNU systems also correspond to this version. */
58 # define __POSIX2_THIS_VERSION 200112L
59 #elif defined __USE_POSIX199506
60 /* The utilities on GNU systems also correspond to this version. */
61 # define __POSIX2_THIS_VERSION 199506L
63 /* The utilities on GNU systems also correspond to this version. */
64 # define __POSIX2_THIS_VERSION 199209L
67 /* The utilities on GNU systems also correspond to this version. */
68 #define _POSIX2_VERSION __POSIX2_THIS_VERSION
70 /* If defined, the implementation supports the
71 C Language Bindings Option. */
72 #define _POSIX2_C_BIND __POSIX2_THIS_VERSION
74 /* If defined, the implementation supports the
75 C Language Development Utilities Option. */
76 #define _POSIX2_C_DEV __POSIX2_THIS_VERSION
78 /* If defined, the implementation supports the
79 Software Development Utilities Option. */
80 #define _POSIX2_SW_DEV __POSIX2_THIS_VERSION
82 /* If defined, the implementation supports the
83 creation of locales with the localedef utility. */
84 #define _POSIX2_LOCALEDEF __POSIX2_THIS_VERSION
86 /* X/Open version number to which the library conforms. It is selectable. */
88 # define _XOPEN_VERSION 700
89 #elif defined __USE_XOPEN2K
90 # define _XOPEN_VERSION 600
91 #elif defined __USE_UNIX98
92 # define _XOPEN_VERSION 500
94 # define _XOPEN_VERSION 4
97 /* Commands and utilities from XPG4 are available. */
98 #define _XOPEN_XCU_VERSION 4
100 /* We are compatible with the old published standards as well. */
101 #define _XOPEN_XPG2 1
102 #define _XOPEN_XPG3 1
103 #define _XOPEN_XPG4 1
105 /* The X/Open Unix extensions are available. */
106 #define _XOPEN_UNIX 1
108 /* Encryption is present. */
109 #define _XOPEN_CRYPT 1
111 /* The enhanced internationalization capabilities according to XPG4.2
113 #define _XOPEN_ENH_I18N 1
115 /* The legacy interfaces are also available. */
116 #define _XOPEN_LEGACY 1
119 /* Get values of POSIX options:
121 If these symbols are defined, the corresponding features are
122 always available. If not, they may be available sometimes.
123 The current values can be obtained with `sysconf'.
125 _POSIX_JOB_CONTROL Job control is supported.
126 _POSIX_SAVED_IDS Processes have a saved set-user-ID
127 and a saved set-group-ID.
128 _POSIX_REALTIME_SIGNALS Real-time, queued signals are supported.
129 _POSIX_PRIORITY_SCHEDULING Priority scheduling is supported.
130 _POSIX_TIMERS POSIX.4 clocks and timers are supported.
131 _POSIX_ASYNCHRONOUS_IO Asynchronous I/O is supported.
132 _POSIX_PRIORITIZED_IO Prioritized asynchronous I/O is supported.
133 _POSIX_SYNCHRONIZED_IO Synchronizing file data is supported.
134 _POSIX_FSYNC The fsync function is present.
135 _POSIX_MAPPED_FILES Mapping of files to memory is supported.
136 _POSIX_MEMLOCK Locking of all memory is supported.
137 _POSIX_MEMLOCK_RANGE Locking of ranges of memory is supported.
138 _POSIX_MEMORY_PROTECTION Setting of memory protections is supported.
139 _POSIX_MESSAGE_PASSING POSIX.4 message queues are supported.
140 _POSIX_SEMAPHORES POSIX.4 counting semaphores are supported.
141 _POSIX_SHARED_MEMORY_OBJECTS POSIX.4 shared memory objects are supported.
142 _POSIX_THREADS POSIX.1c pthreads are supported.
143 _POSIX_THREAD_ATTR_STACKADDR Thread stack address attribute option supported.
144 _POSIX_THREAD_ATTR_STACKSIZE Thread stack size attribute option supported.
145 _POSIX_THREAD_SAFE_FUNCTIONS Thread-safe functions are supported.
146 _POSIX_THREAD_PRIORITY_SCHEDULING
147 POSIX.1c thread execution scheduling supported.
148 _POSIX_THREAD_PRIO_INHERIT Thread priority inheritance option supported.
149 _POSIX_THREAD_PRIO_PROTECT Thread priority protection option supported.
150 _POSIX_THREAD_PROCESS_SHARED Process-shared synchronization supported.
151 _POSIX_PII Protocol-independent interfaces are supported.
152 _POSIX_PII_XTI XTI protocol-indep. interfaces are supported.
153 _POSIX_PII_SOCKET Socket protocol-indep. interfaces are supported.
154 _POSIX_PII_INTERNET Internet family of protocols supported.
155 _POSIX_PII_INTERNET_STREAM Connection-mode Internet protocol supported.
156 _POSIX_PII_INTERNET_DGRAM Connectionless Internet protocol supported.
157 _POSIX_PII_OSI ISO/OSI family of protocols supported.
158 _POSIX_PII_OSI_COTS Connection-mode ISO/OSI service supported.
159 _POSIX_PII_OSI_CLTS Connectionless ISO/OSI service supported.
160 _POSIX_POLL Implementation supports `poll' function.
161 _POSIX_SELECT Implementation supports `select' and `pselect'.
163 _XOPEN_REALTIME X/Open realtime support is available.
164 _XOPEN_REALTIME_THREADS X/Open realtime thread support is available.
165 _XOPEN_SHM Shared memory interface according to XPG4.2.
167 _XBS5_ILP32_OFF32 Implementation provides environment with 32-bit
168 int, long, pointer, and off_t types.
169 _XBS5_ILP32_OFFBIG Implementation provides environment with 32-bit
170 int, long, and pointer and off_t with at least
172 _XBS5_LP64_OFF64 Implementation provides environment with 32-bit
173 int, and 64-bit long, pointer, and off_t types.
174 _XBS5_LPBIG_OFFBIG Implementation provides environment with at
175 least 32 bits int and long, pointer, and off_t
176 with at least 64 bits.
178 If any of these symbols is defined as -1, the corresponding option is not
179 true for any file. If any is defined as other than -1, the corresponding
180 option is true for all files. If a symbol is not defined at all, the value
181 for a specific file can be obtained from `pathconf' and `fpathconf'.
183 _POSIX_CHOWN_RESTRICTED Only the super user can use `chown' to change
184 the owner of a file. `chown' can only be used
185 to change the group ID of a file to a group of
186 which the calling process is a member.
187 _POSIX_NO_TRUNC Pathname components longer than
188 NAME_MAX generate an error.
189 _POSIX_VDISABLE If defined, if the value of an element of the
190 `c_cc' member of `struct termios' is
191 _POSIX_VDISABLE, no character will have the
192 effect associated with that element.
193 _POSIX_SYNC_IO Synchronous I/O may be performed.
194 _POSIX_ASYNC_IO Asynchronous I/O may be performed.
195 _POSIX_PRIO_IO Prioritized Asynchronous I/O may be performed.
197 Support for the Large File Support interface is not generally available.
198 If it is available the following constants are defined to one.
199 _LFS64_LARGEFILE Low-level I/O supports large files.
200 _LFS64_STDIO Standard I/O supports large files.
203 #include <bits/posix_opt.h>
205 /* Get the environment definitions from Unix98. */
206 #if defined __USE_UNIX98 || defined __USE_XOPEN2K
207 # include <bits/environments.h>
210 /* Standard file descriptors. */
211 #define STDIN_FILENO 0 /* Standard input. */
212 #define STDOUT_FILENO 1 /* Standard output. */
213 #define STDERR_FILENO 2 /* Standard error output. */
216 /* All functions that are not declared anywhere else. */
218 #include <bits/types.h>
220 #ifndef __ssize_t_defined
221 typedef __ssize_t ssize_t;
222 # define __ssize_t_defined
225 #define __need_size_t
229 #if defined __USE_XOPEN || defined __USE_XOPEN2K
230 /* The Single Unix specification says that some more types are
232 # ifndef __gid_t_defined
233 typedef __gid_t gid_t;
234 # define __gid_t_defined
237 # ifndef __uid_t_defined
238 typedef __uid_t uid_t;
239 # define __uid_t_defined
242 # ifndef __off_t_defined
243 # ifndef __USE_FILE_OFFSET64
244 typedef __off_t off_t;
246 typedef __off64_t off_t;
248 # define __off_t_defined
250 # if defined __USE_LARGEFILE64 && !defined __off64_t_defined
251 typedef __off64_t off64_t;
252 # define __off64_t_defined
255 # ifndef __useconds_t_defined
256 typedef __useconds_t useconds_t;
257 # define __useconds_t_defined
260 # ifndef __pid_t_defined
261 typedef __pid_t pid_t;
262 # define __pid_t_defined
266 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
267 # ifndef __intptr_t_defined
268 typedef __intptr_t intptr_t;
269 # define __intptr_t_defined
273 #if defined __USE_BSD || defined __USE_XOPEN
274 # ifndef __socklen_t_defined
275 typedef __socklen_t socklen_t;
276 # define __socklen_t_defined
280 /* Values for the second argument to access.
281 These may be OR'd together. */
282 #define R_OK 4 /* Test for read permission. */
283 #define W_OK 2 /* Test for write permission. */
284 #define X_OK 1 /* Test for execute permission. */
285 #define F_OK 0 /* Test for existence. */
287 /* Test for access to NAME using the real UID and real GID. */
288 extern int access (__const char *__name, int __type) __THROW __nonnull ((1));
291 /* Test for access to NAME using the effective UID and GID
292 (as normal file operations use). */
293 extern int euidaccess (__const char *__name, int __type)
294 __THROW __nonnull ((1));
296 /* An alias for `euidaccess', used by some other systems. */
297 extern int eaccess (__const char *__name, int __type)
298 __THROW __nonnull ((1));
302 /* Test for access to FILE relative to the directory FD is open on.
303 If AT_EACCESS is set in FLAG, then use effective IDs like `eaccess',
304 otherwise use real IDs like `access'. */
305 extern int faccessat (int __fd, __const char *__file, int __type, int __flag)
306 __THROW __nonnull ((2)) __wur;
307 #endif /* Use GNU. */
310 /* Values for the WHENCE argument to lseek. */
311 #ifndef _STDIO_H /* <stdio.h> has the same definitions. */
312 # define SEEK_SET 0 /* Seek from beginning of file. */
313 # define SEEK_CUR 1 /* Seek from current position. */
314 # define SEEK_END 2 /* Seek from end of file. */
317 #if defined __USE_BSD && !defined L_SET
318 /* Old BSD names for the same constants; just for compatibility. */
319 # define L_SET SEEK_SET
320 # define L_INCR SEEK_CUR
321 # define L_XTND SEEK_END
325 /* Move FD's file position to OFFSET bytes from the
326 beginning of the file (if WHENCE is SEEK_SET),
327 the current position (if WHENCE is SEEK_CUR),
328 or the end of the file (if WHENCE is SEEK_END).
329 Return the new file position. */
330 #ifndef __USE_FILE_OFFSET64
331 extern __off_t lseek (int __fd, __off_t __offset, int __whence) __THROW;
333 # ifdef __REDIRECT_NTH
334 extern __off64_t __REDIRECT_NTH (lseek,
335 (int __fd, __off64_t __offset, int __whence),
338 # define lseek lseek64
341 #ifdef __USE_LARGEFILE64
342 extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence)
346 /* Close the file descriptor FD.
348 This function is a cancellation point and therefore not marked with
350 extern int close (int __fd);
352 /* Read NBYTES into BUF from FD. Return the
353 number read, -1 for errors or 0 for EOF.
355 This function is a cancellation point and therefore not marked with
357 extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __wur;
359 /* Write N bytes of BUF to FD. Return the number written, or -1.
361 This function is a cancellation point and therefore not marked with
363 extern ssize_t write (int __fd, __const void *__buf, size_t __n) __wur;
365 #if defined __USE_UNIX98 || defined __USE_XOPEN2K8
366 # ifndef __USE_FILE_OFFSET64
367 /* Read NBYTES into BUF from FD at the given position OFFSET without
368 changing the file pointer. Return the number read, -1 for errors
371 This function is a cancellation point and therefore not marked with
373 extern ssize_t pread (int __fd, void *__buf, size_t __nbytes,
374 __off_t __offset) __wur;
376 /* Write N bytes of BUF to FD at the given position OFFSET without
377 changing the file pointer. Return the number written, or -1.
379 This function is a cancellation point and therefore not marked with
381 extern ssize_t pwrite (int __fd, __const void *__buf, size_t __n,
382 __off_t __offset) __wur;
385 extern ssize_t __REDIRECT (pread, (int __fd, void *__buf, size_t __nbytes,
388 extern ssize_t __REDIRECT (pwrite, (int __fd, __const void *__buf,
389 size_t __nbytes, __off64_t __offset),
392 # define pread pread64
393 # define pwrite pwrite64
397 # ifdef __USE_LARGEFILE64
398 /* Read NBYTES into BUF from FD at the given position OFFSET without
399 changing the file pointer. Return the number read, -1 for errors
401 extern ssize_t pread64 (int __fd, void *__buf, size_t __nbytes,
402 __off64_t __offset) __wur;
403 /* Write N bytes of BUF to FD at the given position OFFSET without
404 changing the file pointer. Return the number written, or -1. */
405 extern ssize_t pwrite64 (int __fd, __const void *__buf, size_t __n,
406 __off64_t __offset) __wur;
410 /* Create a one-way communication channel (pipe).
411 If successful, two file descriptors are stored in PIPEDES;
412 bytes written on PIPEDES[1] can be read from PIPEDES[0].
413 Returns 0 if successful, -1 if not. */
414 extern int pipe (int __pipedes[2]) __THROW __wur;
417 /* Same as pipe but apply flags passed in FLAGS to the new file
419 extern int pipe2 (int __pipedes[2], int __flags) __THROW __wur;
422 /* Schedule an alarm. In SECONDS seconds, the process will get a SIGALRM.
423 If SECONDS is zero, any currently scheduled alarm will be cancelled.
424 The function returns the number of seconds remaining until the last
425 alarm scheduled would have signaled, or zero if there wasn't one.
426 There is no return value to indicate an error, but you can set `errno'
427 to 0 and check its value after calling `alarm', and this might tell you.
428 The signal may come late due to processor scheduling. */
429 extern unsigned int alarm (unsigned int __seconds) __THROW;
431 /* Make the process sleep for SECONDS seconds, or until a signal arrives
432 and is not ignored. The function returns the number of seconds less
433 than SECONDS which it actually slept (thus zero if it slept the full time).
434 If a signal handler does a `longjmp' or modifies the handling of the
435 SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
436 signal afterwards is undefined. There is no return value to indicate
437 error, but if `sleep' returns SECONDS, it probably didn't work.
439 This function is a cancellation point and therefore not marked with
441 extern unsigned int sleep (unsigned int __seconds);
443 #if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
445 /* Set an alarm to go off (generating a SIGALRM signal) in VALUE
446 microseconds. If INTERVAL is nonzero, when the alarm goes off, the
447 timer is reset to go off every INTERVAL microseconds thereafter.
448 Returns the number of microseconds remaining before the alarm. */
449 extern __useconds_t ualarm (__useconds_t __value, __useconds_t __interval)
452 /* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
455 This function is a cancellation point and therefore not marked with
457 extern int usleep (__useconds_t __useconds);
461 /* Suspend the process until a signal arrives.
462 This always returns -1 and sets `errno' to EINTR.
464 This function is a cancellation point and therefore not marked with
466 extern int pause (void);
469 /* Change the owner and group of FILE. */
470 extern int chown (__const char *__file, __uid_t __owner, __gid_t __group)
471 __THROW __nonnull ((1)) __wur;
473 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
474 /* Change the owner and group of the file that FD is open on. */
475 extern int fchown (int __fd, __uid_t __owner, __gid_t __group) __THROW __wur;
478 /* Change owner and group of FILE, if it is a symbolic
479 link the ownership of the symbolic link is changed. */
480 extern int lchown (__const char *__file, __uid_t __owner, __gid_t __group)
481 __THROW __nonnull ((1)) __wur;
483 #endif /* Use BSD || X/Open Unix. */
486 /* Change the owner and group of FILE relative to the directory FD is open
488 extern int fchownat (int __fd, __const char *__file, __uid_t __owner,
489 __gid_t __group, int __flag)
490 __THROW __nonnull ((2)) __wur;
491 #endif /* Use GNU. */
493 /* Change the process's working directory to PATH. */
494 extern int chdir (__const char *__path) __THROW __nonnull ((1)) __wur;
496 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
497 /* Change the process's working directory to the one FD is open on. */
498 extern int fchdir (int __fd) __THROW __wur;
501 /* Get the pathname of the current working directory,
502 and put it in SIZE bytes of BUF. Returns NULL if the
503 directory couldn't be determined or SIZE was too small.
504 If successful, returns BUF. In GNU, if BUF is NULL,
505 an array is allocated with `malloc'; the array is SIZE
506 bytes long, unless SIZE == 0, in which case it is as
508 extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
511 /* Return a malloc'd string containing the current directory name.
512 If the environment variable `PWD' is set, and its value is correct,
513 that value is used. */
514 extern char *get_current_dir_name (void) __THROW;
517 #if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
519 /* Put the absolute pathname of the current working directory in BUF.
520 If successful, return BUF. If not, put an error message in
521 BUF and return NULL. BUF should be at least PATH_MAX bytes long. */
522 extern char *getwd (char *__buf)
523 __THROW __nonnull ((1)) __attribute_deprecated__ __wur;
527 /* Duplicate FD, returning a new file descriptor on the same file. */
528 extern int dup (int __fd) __THROW __wur;
530 /* Duplicate FD to FD2, closing FD2 and making it open on the same file. */
531 extern int dup2 (int __fd, int __fd2) __THROW;
534 /* Duplicate FD to FD2, closing FD2 and making it open on the same
535 file while setting flags according to FLAGS. */
536 extern int dup3 (int __fd, int __fd2, int __flags) __THROW;
539 /* NULL-terminated array of "NAME=VALUE" environment variables. */
540 extern char **__environ;
542 extern char **environ;
546 /* Replace the current process, executing PATH with arguments ARGV and
547 environment ENVP. ARGV and ENVP are terminated by NULL pointers. */
548 extern int execve (__const char *__path, char *__const __argv[],
549 char *__const __envp[]) __THROW __nonnull ((1, 2));
551 #ifdef __USE_XOPEN2K8
552 /* Execute the file FD refers to, overlaying the running program image.
553 ARGV and ENVP are passed to the new program, as for `execve'. */
554 extern int fexecve (int __fd, char *__const __argv[], char *__const __envp[])
555 __THROW __nonnull ((2));
559 /* Execute PATH with arguments ARGV and environment from `environ'. */
560 extern int execv (__const char *__path, char *__const __argv[])
561 __THROW __nonnull ((1, 2));
563 /* Execute PATH with all arguments after PATH until a NULL pointer,
564 and the argument after that for environment. */
565 extern int execle (__const char *__path, __const char *__arg, ...)
566 __THROW __nonnull ((1, 2));
568 /* Execute PATH with all arguments after PATH until
569 a NULL pointer and environment from `environ'. */
570 extern int execl (__const char *__path, __const char *__arg, ...)
571 __THROW __nonnull ((1, 2));
573 /* Execute FILE, searching in the `PATH' environment variable if it contains
574 no slashes, with arguments ARGV and environment from `environ'. */
575 extern int execvp (__const char *__file, char *__const __argv[])
576 __THROW __nonnull ((1, 2));
578 /* Execute FILE, searching in the `PATH' environment variable if
579 it contains no slashes, with all arguments after FILE until a
580 NULL pointer and environment from `environ'. */
581 extern int execlp (__const char *__file, __const char *__arg, ...)
582 __THROW __nonnull ((1, 2));
585 /* Execute FILE, searching in the `PATH' environment variable if it contains
586 no slashes, with arguments ARGV and environment from `environ'. */
587 extern int execvpe (__const char *__file, char *__const __argv[],
588 char *__const __envp[])
589 __THROW __nonnull ((1, 2));
593 #if defined __USE_MISC || defined __USE_XOPEN
594 /* Add INC to priority of the current process. */
595 extern int nice (int __inc) __THROW __wur;
599 /* Terminate program execution with the low-order 8 bits of STATUS. */
600 extern void _exit (int __status) __attribute__ ((__noreturn__));
603 /* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
604 the `_SC_*' symbols for the NAME argument to `sysconf';
605 and the `_CS_*' symbols for the NAME argument to `confstr'. */
606 #include <bits/confname.h>
608 /* Get file-specific configuration information about PATH. */
609 extern long int pathconf (__const char *__path, int __name)
610 __THROW __nonnull ((1));
612 /* Get file-specific configuration about descriptor FD. */
613 extern long int fpathconf (int __fd, int __name) __THROW;
615 /* Get the value of the system variable NAME. */
616 extern long int sysconf (int __name) __THROW;
619 /* Get the value of the string-valued system variable NAME. */
620 extern size_t confstr (int __name, char *__buf, size_t __len) __THROW;
624 /* Get the process ID of the calling process. */
625 extern __pid_t getpid (void) __THROW;
627 /* Get the process ID of the calling process's parent. */
628 extern __pid_t getppid (void) __THROW;
630 /* Get the process group ID of the calling process.
631 This function is different on old BSD. */
633 extern __pid_t getpgrp (void) __THROW;
635 # ifdef __REDIRECT_NTH
636 extern __pid_t __REDIRECT_NTH (getpgrp, (__pid_t __pid), __getpgid);
638 # define getpgrp __getpgid
642 /* Get the process group ID of process PID. */
643 extern __pid_t __getpgid (__pid_t __pid) __THROW;
644 #if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
645 extern __pid_t getpgid (__pid_t __pid) __THROW;
649 /* Set the process group ID of the process matching PID to PGID.
650 If PID is zero, the current process's process group ID is set.
651 If PGID is zero, the process ID of the process is used. */
652 extern int setpgid (__pid_t __pid, __pid_t __pgid) __THROW;
654 #if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED
655 /* Both System V and BSD have `setpgrp' functions, but with different
656 calling conventions. The BSD function is the same as POSIX.1 `setpgid'
657 (above). The System V function takes no arguments and puts the calling
658 process in its on group like `setpgid (0, 0)'.
660 New programs should always use `setpgid' instead.
662 The default in GNU is to provide the System V function. The BSD
663 function is available under -D_BSD_SOURCE. */
667 /* Set the process group ID of the calling process to its own PID.
668 This is exactly the same as `setpgid (0, 0)'. */
669 extern int setpgrp (void) __THROW;
673 /* Another name for `setpgid' (above). */
674 # ifdef __REDIRECT_NTH
675 extern int __REDIRECT_NTH (setpgrp, (__pid_t __pid, __pid_t __pgrp), setpgid);
677 # define setpgrp setpgid
680 # endif /* Favor BSD. */
681 #endif /* Use SVID or BSD. */
683 /* Create a new session with the calling process as its leader.
684 The process group IDs of the session and the calling process
685 are set to the process ID of the calling process, which is returned. */
686 extern __pid_t setsid (void) __THROW;
688 #if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
689 /* Return the session ID of the given process. */
690 extern __pid_t getsid (__pid_t __pid) __THROW;
693 /* Get the real user ID of the calling process. */
694 extern __uid_t getuid (void) __THROW;
696 /* Get the effective user ID of the calling process. */
697 extern __uid_t geteuid (void) __THROW;
699 /* Get the real group ID of the calling process. */
700 extern __gid_t getgid (void) __THROW;
702 /* Get the effective group ID of the calling process. */
703 extern __gid_t getegid (void) __THROW;
705 /* If SIZE is zero, return the number of supplementary groups
706 the calling process is in. Otherwise, fill in the group IDs
707 of its supplementary groups in LIST and return the number written. */
708 extern int getgroups (int __size, __gid_t __list[]) __THROW __wur;
711 /* Return nonzero iff the calling process is in group GID. */
712 extern int group_member (__gid_t __gid) __THROW;
715 /* Set the user ID of the calling process to UID.
716 If the calling process is the super-user, set the real
717 and effective user IDs, and the saved set-user-ID to UID;
718 if not, the effective user ID is set to UID. */
719 extern int setuid (__uid_t __uid) __THROW;
721 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
722 /* Set the real user ID of the calling process to RUID,
723 and the effective user ID of the calling process to EUID. */
724 extern int setreuid (__uid_t __ruid, __uid_t __euid) __THROW;
727 #if defined __USE_BSD || defined __USE_XOPEN2K
728 /* Set the effective user ID of the calling process to UID. */
729 extern int seteuid (__uid_t __uid) __THROW;
730 #endif /* Use BSD. */
732 /* Set the group ID of the calling process to GID.
733 If the calling process is the super-user, set the real
734 and effective group IDs, and the saved set-group-ID to GID;
735 if not, the effective group ID is set to GID. */
736 extern int setgid (__gid_t __gid) __THROW;
738 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
739 /* Set the real group ID of the calling process to RGID,
740 and the effective group ID of the calling process to EGID. */
741 extern int setregid (__gid_t __rgid, __gid_t __egid) __THROW;
744 #if defined __USE_BSD || defined __USE_XOPEN2K
745 /* Set the effective group ID of the calling process to GID. */
746 extern int setegid (__gid_t __gid) __THROW;
747 #endif /* Use BSD. */
750 /* Fetch the real user ID, effective user ID, and saved-set user ID,
751 of the calling process. */
752 extern int getresuid (__uid_t *__ruid, __uid_t *__euid, __uid_t *__suid)
755 /* Fetch the real group ID, effective group ID, and saved-set group ID,
756 of the calling process. */
757 extern int getresgid (__gid_t *__rgid, __gid_t *__egid, __gid_t *__sgid)
760 /* Set the real user ID, effective user ID, and saved-set user ID,
761 of the calling process to RUID, EUID, and SUID, respectively. */
762 extern int setresuid (__uid_t __ruid, __uid_t __euid, __uid_t __suid)
765 /* Set the real group ID, effective group ID, and saved-set group ID,
766 of the calling process to RGID, EGID, and SGID, respectively. */
767 extern int setresgid (__gid_t __rgid, __gid_t __egid, __gid_t __sgid)
772 /* Clone the calling process, creating an exact copy.
773 Return -1 for errors, 0 to the new process,
774 and the process ID of the new process to the old process. */
775 extern __pid_t fork (void) __THROW;
777 #if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
779 /* Clone the calling process, but without copying the whole address space.
780 The calling process is suspended until the new process exits or is
781 replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
782 and the process ID of the new process to the old process. */
783 extern __pid_t vfork (void) __THROW;
784 #endif /* Use BSD or XPG < 7. */
787 /* Return the pathname of the terminal FD is open on, or NULL on errors.
788 The returned storage is good only until the next call to this function. */
789 extern char *ttyname (int __fd) __THROW;
791 /* Store at most BUFLEN characters of the pathname of the terminal FD is
792 open on in BUF. Return 0 on success, otherwise an error number. */
793 extern int ttyname_r (int __fd, char *__buf, size_t __buflen)
794 __THROW __nonnull ((2)) __wur;
796 /* Return 1 if FD is a valid descriptor associated
797 with a terminal, zero if not. */
798 extern int isatty (int __fd) __THROW;
800 #if defined __USE_BSD \
801 || (defined __USE_XOPEN_EXTENDED && !defined __USE_UNIX98)
802 /* Return the index into the active-logins file (utmp) for
803 the controlling terminal. */
804 extern int ttyslot (void) __THROW;
808 /* Make a link to FROM named TO. */
809 extern int link (__const char *__from, __const char *__to)
810 __THROW __nonnull ((1, 2)) __wur;
813 /* Like link but relative paths in TO and FROM are interpreted relative
814 to FROMFD and TOFD respectively. */
815 extern int linkat (int __fromfd, __const char *__from, int __tofd,
816 __const char *__to, int __flags)
817 __THROW __nonnull ((2, 4)) __wur;
820 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
821 /* Make a symbolic link to FROM named TO. */
822 extern int symlink (__const char *__from, __const char *__to)
823 __THROW __nonnull ((1, 2)) __wur;
825 /* Read the contents of the symbolic link PATH into no more than
826 LEN bytes of BUF. The contents are not null-terminated.
827 Returns the number of characters read, or -1 for errors. */
828 extern ssize_t readlink (__const char *__restrict __path,
829 char *__restrict __buf, size_t __len)
830 __THROW __nonnull ((1, 2)) __wur;
831 #endif /* Use BSD. */
834 /* Like symlink but a relative path in TO is interpreted relative to TOFD. */
835 extern int symlinkat (__const char *__from, int __tofd,
836 __const char *__to) __THROW __nonnull ((1, 3)) __wur;
838 /* Like readlink but a relative PATH is interpreted relative to FD. */
839 extern ssize_t readlinkat (int __fd, __const char *__restrict __path,
840 char *__restrict __buf, size_t __len)
841 __THROW __nonnull ((2, 3)) __wur;
844 /* Remove the link NAME. */
845 extern int unlink (__const char *__name) __THROW __nonnull ((1));
848 /* Remove the link NAME relative to FD. */
849 extern int unlinkat (int __fd, __const char *__name, int __flag)
850 __THROW __nonnull ((2));
853 /* Remove the directory PATH. */
854 extern int rmdir (__const char *__path) __THROW __nonnull ((1));
857 /* Return the foreground process group ID of FD. */
858 extern __pid_t tcgetpgrp (int __fd) __THROW;
860 /* Set the foreground process group ID of FD set PGRP_ID. */
861 extern int tcsetpgrp (int __fd, __pid_t __pgrp_id) __THROW;
864 /* Return the login name of the user.
866 This function is a possible cancellation point and therefore not
867 marked with __THROW. */
868 extern char *getlogin (void);
869 #if defined __USE_REENTRANT || defined __USE_POSIX199506
870 /* Return at most NAME_LEN characters of the login name of the user in NAME.
871 If it cannot be determined or some other error occurred, return the error
872 code. Otherwise return 0.
874 This function is a possible cancellation point and therefore not
875 marked with __THROW. */
876 extern int getlogin_r (char *__name, size_t __name_len) __nonnull ((1));
880 /* Set the login name returned by `getlogin'. */
881 extern int setlogin (__const char *__name) __THROW __nonnull ((1));
886 /* Get definitions and prototypes for functions to process the
887 arguments in ARGV (ARGC of them, minus the program name) for
888 options given in OPTS. */
889 # define __need_getopt
894 #if defined __USE_BSD || defined __USE_UNIX98 || defined __USE_XOPEN2K
895 /* Put the name of the current host in no more than LEN bytes of NAME.
896 The result is null-terminated if LEN is large enough for the full
897 name and the terminator. */
898 extern int gethostname (char *__name, size_t __len) __THROW __nonnull ((1));
902 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_UNIX98)
903 /* Set the name of the current host to NAME, which is LEN bytes long.
904 This call is restricted to the super-user. */
905 extern int sethostname (__const char *__name, size_t __len)
906 __THROW __nonnull ((1)) __wur;
908 /* Set the current machine's Internet number to ID.
909 This call is restricted to the super-user. */
910 extern int sethostid (long int __id) __THROW __wur;
913 /* Get and set the NIS (aka YP) domain name, if any.
914 Called just like `gethostname' and `sethostname'.
915 The NIS domain name is usually the empty string when not using NIS. */
916 extern int getdomainname (char *__name, size_t __len)
917 __THROW __nonnull ((1)) __wur;
918 extern int setdomainname (__const char *__name, size_t __len)
919 __THROW __nonnull ((1)) __wur;
922 /* Revoke access permissions to all processes currently communicating
923 with the control terminal, and then send a SIGHUP signal to the process
924 group of the control terminal. */
925 extern int vhangup (void) __THROW;
927 /* Revoke the access of all descriptors currently open on FILE. */
928 extern int revoke (__const char *__file) __THROW __nonnull ((1)) __wur;
931 /* Enable statistical profiling, writing samples of the PC into at most
932 SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
933 is enabled, the system examines the user PC and increments
934 SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536]. If SCALE is zero,
935 disable profiling. Returns zero on success, -1 on error. */
936 extern int profil (unsigned short int *__sample_buffer, size_t __size,
937 size_t __offset, unsigned int __scale)
938 __THROW __nonnull ((1));
941 /* Turn accounting on if NAME is an existing file. The system will then write
942 a record for each process as it terminates, to this file. If NAME is NULL,
943 turn accounting off. This call is restricted to the super-user. */
944 extern int acct (__const char *__name) __THROW;
947 /* Successive calls return the shells listed in `/etc/shells'. */
948 extern char *getusershell (void) __THROW;
949 extern void endusershell (void) __THROW; /* Discard cached info. */
950 extern void setusershell (void) __THROW; /* Rewind and re-read the file. */
953 /* Put the program in the background, and dissociate from the controlling
954 terminal. If NOCHDIR is zero, do `chdir ("/")'. If NOCLOSE is zero,
955 redirects stdin, stdout, and stderr to /dev/null. */
956 extern int daemon (int __nochdir, int __noclose) __THROW __wur;
957 #endif /* Use BSD || X/Open. */
960 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
961 /* Make PATH be the root directory (the starting point for absolute paths).
962 This call is restricted to the super-user. */
963 extern int chroot (__const char *__path) __THROW __nonnull ((1)) __wur;
965 /* Prompt with PROMPT and read a string from the terminal without echoing.
966 Uses /dev/tty if possible; otherwise stderr and stdin. */
967 extern char *getpass (__const char *__prompt) __nonnull ((1));
968 #endif /* Use BSD || X/Open. */
971 #if defined __USE_BSD || defined __USE_XOPEN || defined __USE_XOPEN2K
972 /* Make all changes done to FD actually appear on disk.
974 This function is a cancellation point and therefore not marked with
976 extern int fsync (int __fd);
977 #endif /* Use BSD || X/Open || Unix98. */
981 /* Make all changes done to all files on the file system associated
982 with FD actually appear on disk. */
983 extern int syncfs (int __fd) __THROW;
987 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
989 /* Return identifier for the current host. */
990 extern long int gethostid (void);
992 /* Make all changes done to all files actually appear on disk. */
993 extern void sync (void) __THROW;
996 # if defined __USE_BSD || !defined __USE_XOPEN2K
997 /* Return the number of bytes in a page. This is the system's page size,
998 which is not necessarily the same as the hardware page size. */
999 extern int getpagesize (void) __THROW __attribute__ ((__const__));
1002 /* Return the maximum number of file descriptors
1003 the current process could possibly have. */
1004 extern int getdtablesize (void) __THROW;
1007 #endif /* Use BSD || X/Open Unix. */
1010 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
1012 /* Truncate FILE to LENGTH bytes. */
1013 # ifndef __USE_FILE_OFFSET64
1014 extern int truncate (__const char *__file, __off_t __length)
1015 __THROW __nonnull ((1)) __wur;
1017 # ifdef __REDIRECT_NTH
1018 extern int __REDIRECT_NTH (truncate,
1019 (__const char *__file, __off64_t __length),
1020 truncate64) __nonnull ((1)) __wur;
1022 # define truncate truncate64
1025 # ifdef __USE_LARGEFILE64
1026 extern int truncate64 (__const char *__file, __off64_t __length)
1027 __THROW __nonnull ((1)) __wur;
1030 #endif /* Use BSD || X/Open Unix || POSIX 2008. */
1032 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
1034 /* Truncate the file FD is open on to LENGTH bytes. */
1035 # ifndef __USE_FILE_OFFSET64
1036 extern int ftruncate (int __fd, __off_t __length) __THROW __wur;
1038 # ifdef __REDIRECT_NTH
1039 extern int __REDIRECT_NTH (ftruncate, (int __fd, __off64_t __length),
1042 # define ftruncate ftruncate64
1045 # ifdef __USE_LARGEFILE64
1046 extern int ftruncate64 (int __fd, __off64_t __length) __THROW __wur;
1049 #endif /* Use BSD || X/Open Unix || POSIX 2003. */
1052 #if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K) \
1053 || defined __USE_MISC
1055 /* Set the end of accessible data space (aka "the break") to ADDR.
1056 Returns zero on success and -1 for errors (with errno set). */
1057 extern int brk (void *__addr) __THROW __wur;
1059 /* Increase or decrease the end of accessible data space by DELTA bytes.
1060 If successful, returns the address the previous end of data space
1061 (i.e. the beginning of the new space, if DELTA > 0);
1062 returns (void *) -1 for errors (with errno set). */
1063 extern void *sbrk (intptr_t __delta) __THROW;
1068 /* Invoke `system call' number SYSNO, passing it the remaining arguments.
1069 This is completely system-dependent, and not often useful.
1071 In Unix, `syscall' sets `errno' for all errors and most calls return -1
1072 for errors; in many systems you cannot pass arguments or get return
1073 values for all system calls (`pipe', `fork', and `getppid' typically
1076 In Mach, all system calls take normal arguments and always return an
1077 error code (zero for success). */
1078 extern long int syscall (long int __sysno, ...) __THROW;
1080 #endif /* Use misc. */
1083 #if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
1084 /* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
1085 files consistent. Some systems have them there and some here, and some
1086 software depends on the macros being defined without including both. */
1088 /* `lockf' is a simpler interface to the locking facilities of `fcntl'.
1089 LEN is always relative to the current file position.
1090 The CMD argument is one of the following.
1092 This function is a cancellation point and therefore not marked with
1095 # define F_ULOCK 0 /* Unlock a previously locked region. */
1096 # define F_LOCK 1 /* Lock a region for exclusive use. */
1097 # define F_TLOCK 2 /* Test and lock a region for exclusive use. */
1098 # define F_TEST 3 /* Test a region for other processes locks. */
1100 # ifndef __USE_FILE_OFFSET64
1101 extern int lockf (int __fd, int __cmd, __off_t __len) __wur;
1104 extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len),
1107 # define lockf lockf64
1110 # ifdef __USE_LARGEFILE64
1111 extern int lockf64 (int __fd, int __cmd, __off64_t __len) __wur;
1113 #endif /* Use misc and F_LOCK not already defined. */
1118 /* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
1121 # define TEMP_FAILURE_RETRY(expression) \
1123 ({ long int __result; \
1124 do __result = (long int) (expression); \
1125 while (__result == -1L && errno == EINTR); \
1129 #if defined __USE_POSIX199309 || defined __USE_UNIX98
1130 /* Synchronize at least the data part of a file with the underlying
1132 extern int fdatasync (int __fildes);
1133 #endif /* Use POSIX199309 */
1136 /* XPG4.2 specifies that prototypes for the encryption functions must
1139 /* Encrypt at most 8 characters from KEY using salt to perturb DES. */
1140 extern char *crypt (__const char *__key, __const char *__salt)
1141 __THROW __nonnull ((1, 2));
1143 /* Encrypt data in BLOCK in place if EDFLAG is zero; otherwise decrypt
1145 extern void encrypt (char *__block, int __edflag) __THROW __nonnull ((1));
1148 /* Swab pairs bytes in the first N bytes of the area pointed to by
1149 FROM and copy the result to TO. The value of TO must not be in the
1150 range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
1151 is without partner. */
1152 extern void swab (__const void *__restrict __from, void *__restrict __to,
1153 ssize_t __n) __THROW __nonnull ((1, 2));
1157 /* The Single Unix specification demands this prototype to be here.
1158 It is also found in <stdio.h>. */
1159 #if defined __USE_XOPEN || defined __USE_XOPEN2K8
1160 /* Return the name of the controlling terminal. */
1161 extern char *ctermid (char *__s) __THROW;
1165 /* Define some macros helping to catch buffer overflows. */
1166 #if __USE_FORTIFY_LEVEL > 0 && defined __extern_always_inline
1167 # include <bits/unistd.h>
1172 #endif /* unistd.h */