1 /* Copyright (C) 1991-1999, 2000, 2001 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'. */
33 /* POSIX Standard approved as ISO/IEC 9945-1 as of August, 1988 and
34 extended by POSIX-1b (aka POSIX-4) and POSIX-1c (aka POSIX threads). */
35 #define _POSIX_VERSION 199506L
37 /* These are not #ifdef __USE_POSIX2 because they are
38 in the theoretically application-owned namespace. */
40 /* POSIX Standard approved as ISO/IEC 9945-2 as of December, 1993. */
41 #define _POSIX2_C_VERSION 199209L
43 /* The utilities on GNU systems also correspond to this version. */
44 #define _POSIX2_VERSION 199209L
46 /* If defined, the implementation supports the
47 C Language Bindings Option. */
48 #define _POSIX2_C_BIND 1
50 /* If defined, the implementation supports the
51 C Language Development Utilities Option. */
52 #define _POSIX2_C_DEV 1
54 /* If defined, the implementation supports the
55 Software Development Utilities Option. */
56 #define _POSIX2_SW_DEV 1
58 /* If defined, the implementation supports the
59 creation of locales with the localedef utility. */
60 #define _POSIX2_LOCALEDEF 1
62 /* X/Open version number to which the library conforms. It is selectable. */
64 # define _XOPEN_VERSION 500
66 # define _XOPEN_VERSION 4
69 /* Commands and utilities from XPG4 are available. */
70 #define _XOPEN_XCU_VERSION 4
72 /* We are compatible with the old published standards as well. */
77 /* The X/Open Unix extensions are available. */
80 /* Encryption is present. */
81 #define _XOPEN_CRYPT 1
83 /* The enhanced internationalization capabilities according to XPG4.2
85 #define _XOPEN_ENH_I18N 1
87 /* The legacy interfaces are also available. */
88 #define _XOPEN_LEGACY 1
91 /* Get values of POSIX options:
93 If these symbols are defined, the corresponding features are
94 always available. If not, they may be available sometimes.
95 The current values can be obtained with `sysconf'.
97 _POSIX_JOB_CONTROL Job control is supported.
98 _POSIX_SAVED_IDS Processes have a saved set-user-ID
99 and a saved set-group-ID.
100 _POSIX_REALTIME_SIGNALS Real-time, queued signals are supported.
101 _POSIX_PRIORITY_SCHEDULING Priority scheduling is supported.
102 _POSIX_TIMERS POSIX.4 clocks and timers are supported.
103 _POSIX_ASYNCHRONOUS_IO Asynchronous I/O is supported.
104 _POSIX_PRIORITIZED_IO Prioritized asynchronous I/O is supported.
105 _POSIX_SYNCHRONIZED_IO Synchronizing file data is supported.
106 _POSIX_FSYNC The fsync function is present.
107 _POSIX_MAPPED_FILES Mapping of files to memory is supported.
108 _POSIX_MEMLOCK Locking of all memory is supported.
109 _POSIX_MEMLOCK_RANGE Locking of ranges of memory is supported.
110 _POSIX_MEMORY_PROTECTION Setting of memory protections is supported.
111 _POSIX_MESSAGE_PASSING POSIX.4 message queues are supported.
112 _POSIX_SEMAPHORES POSIX.4 counting semaphores are supported.
113 _POSIX_SHARED_MEMORY_OBJECTS POSIX.4 shared memory objects are supported.
114 _POSIX_THREADS POSIX.1c pthreads are supported.
115 _POSIX_THREAD_ATTR_STACKADDR Thread stack address attribute option supported.
116 _POSIX_THREAD_ATTR_STACKSIZE Thread stack size attribute option supported.
117 _POSIX_THREAD_SAFE_FUNCTIONS Thread-safe functions are supported.
118 _POSIX_THREAD_PRIORITY_SCHEDULING
119 POSIX.1c thread execution scheduling supported.
120 _POSIX_THREAD_PRIO_INHERIT Thread priority inheritance option supported.
121 _POSIX_THREAD_PRIO_PROTECT Thread priority protection option supported.
122 _POSIX_THREAD_PROCESS_SHARED Process-shared synchronization supported.
123 _POSIX_PII Protocol-independent interfaces are supported.
124 _POSIX_PII_XTI XTI protocol-indep. interfaces are supported.
125 _POSIX_PII_SOCKET Socket protocol-indep. interfaces are supported.
126 _POSIX_PII_INTERNET Internet family of protocols supported.
127 _POSIX_PII_INTERNET_STREAM Connection-mode Internet protocol supported.
128 _POSIX_PII_INTERNET_DGRAM Connectionless Internet protocol supported.
129 _POSIX_PII_OSI ISO/OSI family of protocols supported.
130 _POSIX_PII_OSI_COTS Connection-mode ISO/OSI service supported.
131 _POSIX_PII_OSI_CLTS Connectionless ISO/OSI service supported.
132 _POSIX_POLL Implementation supports `poll' function.
133 _POSIX_SELECT Implementation supports `select' and `pselect'.
135 _XOPEN_REALTIME X/Open realtime support is available.
136 _XOPEN_REALTIME_THREADS X/Open realtime thread support is available.
137 _XOPEN_SHM Shared memory interface according to XPG4.2.
139 _XBS5_ILP32_OFF32 Implementation provides environment with 32-bit
140 int, long, pointer, and off_t types.
141 _XBS5_ILP32_OFFBIG Implementation provides environment with 32-bit
142 int, long, and pointer and off_t with at least
144 _XBS5_LP64_OFF64 Implementation provides environment with 32-bit
145 int, and 64-bit long, pointer, and off_t types.
146 _XBS5_LPBIG_OFFBIG Implementation provides environment with at
147 least 32 bits int and long, pointer, and off_t
148 with at least 64 bits.
150 If any of these symbols is defined as -1, the corresponding option is not
151 true for any file. If any is defined as other than -1, the corresponding
152 option is true for all files. If a symbol is not defined at all, the value
153 for a specific file can be obtained from `pathconf' and `fpathconf'.
155 _POSIX_CHOWN_RESTRICTED Only the super user can use `chown' to change
156 the owner of a file. `chown' can only be used
157 to change the group ID of a file to a group of
158 which the calling process is a member.
159 _POSIX_NO_TRUNC Pathname components longer than
160 NAME_MAX generate an error.
161 _POSIX_VDISABLE If defined, if the value of an element of the
162 `c_cc' member of `struct termios' is
163 _POSIX_VDISABLE, no character will have the
164 effect associated with that element.
165 _POSIX_SYNC_IO Synchronous I/O may be performed.
166 _POSIX_ASYNC_IO Asynchronous I/O may be performed.
167 _POSIX_PRIO_IO Prioritized Asynchronous I/O may be performed.
169 Support for the Large File Support interface is not generally available.
170 If it is available the following constants are defined to one.
171 _LFS64_LARGEFILE Low-level I/O supports large files.
172 _LFS64_STDIO Standard I/O supports large files.
175 #include <bits/posix_opt.h>
177 /* Get the environment definitions from Unix98. */
179 # include <bits/environments.h>
182 /* Standard file descriptors. */
183 #define STDIN_FILENO 0 /* Standard input. */
184 #define STDOUT_FILENO 1 /* Standard output. */
185 #define STDERR_FILENO 2 /* Standard error output. */
188 /* All functions that are not declared anywhere else. */
190 #include <bits/types.h>
192 #ifndef __ssize_t_defined
193 typedef __ssize_t ssize_t;
194 # define __ssize_t_defined
197 #define __need_size_t
202 /* The Single Unix specification says that some more types are
204 # ifndef __gid_t_defined
205 typedef __gid_t gid_t;
206 # define __gid_t_defined
209 # ifndef __uid_t_defined
210 typedef __uid_t uid_t;
211 # define __uid_t_defined
214 # ifndef __off_t_defined
215 # ifndef __USE_FILE_OFFSET64
216 typedef __off_t off_t;
218 typedef __off64_t off_t;
220 # define __off_t_defined
222 # if defined __USE_LARGEFILE64 && !defined __off64_t_defined
223 typedef __off64_t off64_t;
224 # define __off64_t_defined
227 # ifndef __useconds_t_defined
228 typedef __useconds_t useconds_t;
229 # define __useconds_t_defined
232 # ifndef __pid_t_defined
233 typedef __pid_t pid_t;
234 # define __pid_t_defined
238 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
239 # ifndef __intptr_t_defined
240 typedef __intptr_t intptr_t;
241 # define __intptr_t_defined
245 #if defined __USE_BSD || defined __USE_XOPEN
246 # ifndef __socklen_t_defined
247 typedef __socklen_t socklen_t;
248 # define __socklen_t_defined
252 /* Values for the second argument to access.
253 These may be OR'd together. */
254 #define R_OK 4 /* Test for read permission. */
255 #define W_OK 2 /* Test for write permission. */
256 #define X_OK 1 /* Test for execute permission. */
257 #define F_OK 0 /* Test for existence. */
259 /* Test for access to NAME using the real UID and real GID. */
260 extern int access (__const char *__name, int __type) __THROW;
263 /* Values for the WHENCE argument to lseek. */
264 #ifndef _STDIO_H /* <stdio.h> has the same definitions. */
265 # define SEEK_SET 0 /* Seek from beginning of file. */
266 # define SEEK_CUR 1 /* Seek from current position. */
267 # define SEEK_END 2 /* Seek from end of file. */
270 #if defined __USE_BSD && !defined L_SET
271 /* Old BSD names for the same constants; just for compatibility. */
272 # define L_SET SEEK_SET
273 # define L_INCR SEEK_CUR
274 # define L_XTND SEEK_END
278 /* Move FD's file position to OFFSET bytes from the
279 beginning of the file (if WHENCE is SEEK_SET),
280 the current position (if WHENCE is SEEK_CUR),
281 or the end of the file (if WHENCE is SEEK_END).
282 Return the new file position. */
283 #ifndef __USE_FILE_OFFSET64
284 extern __off_t lseek (int __fd, __off_t __offset, int __whence) __THROW;
287 extern __off64_t __REDIRECT (lseek,
288 (int __fd, __off64_t __offset, int __whence)
292 # define lseek lseek64
295 #ifdef __USE_LARGEFILE64
296 extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence) __THROW;
299 /* Close the file descriptor FD. */
300 extern int close (int __fd) __THROW;
302 /* Read NBYTES into BUF from FD. Return the
303 number read, -1 for errors or 0 for EOF. */
304 extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __THROW;
306 /* Write N bytes of BUF to FD. Return the number written, or -1. */
307 extern ssize_t write (int __fd, __const void *__buf, size_t __n) __THROW;
310 # ifndef __USE_FILE_OFFSET64
311 extern ssize_t pread (int __fd, void *__buf, size_t __nbytes, __off_t __offset)
313 extern ssize_t pwrite (int __fd, __const void *__buf, size_t __n,
314 __off_t __offset) __THROW;
317 extern ssize_t __REDIRECT (pread, (int __fd, void *__buf, size_t __nbytes,
318 __off64_t __offset) __THROW,
320 extern ssize_t __REDIRECT (pwrite, (int __fd, __const void *__buf,
321 size_t __nbytes, __off64_t __offset)
325 # define pread pread64
326 # define pwrite pwrite64
330 # ifdef __USE_LARGEFILE64
331 /* Read NBYTES into BUF from FD at the given position OFFSET without
332 changing the file pointer. Return the number read, -1 for errors
334 extern ssize_t pread64 (int __fd, void *__buf, size_t __nbytes,
335 __off64_t __offset) __THROW;
336 /* Write N bytes of BUF to FD at the given position OFFSET without
337 changing the file pointer. Return the number written, or -1. */
338 extern ssize_t pwrite64 (int __fd, __const void *__buf, size_t __n,
339 __off64_t __offset) __THROW;
343 /* Create a one-way communication channel (pipe).
344 If successful, two file descriptors are stored in PIPEDES;
345 bytes written on PIPEDES[1] can be read from PIPEDES[0].
346 Returns 0 if successful, -1 if not. */
347 extern int pipe (int __pipedes[2]) __THROW;
349 /* Schedule an alarm. In SECONDS seconds, the process will get a SIGALRM.
350 If SECONDS is zero, any currently scheduled alarm will be cancelled.
351 The function returns the number of seconds remaining until the last
352 alarm scheduled would have signaled, or zero if there wasn't one.
353 There is no return value to indicate an error, but you can set `errno'
354 to 0 and check its value after calling `alarm', and this might tell you.
355 The signal may come late due to processor scheduling. */
356 extern unsigned int alarm (unsigned int __seconds) __THROW;
358 /* Make the process sleep for SECONDS seconds, or until a signal arrives
359 and is not ignored. The function returns the number of seconds less
360 than SECONDS which it actually slept (thus zero if it slept the full time).
361 If a signal handler does a `longjmp' or modifies the handling of the
362 SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
363 signal afterwards is undefined. There is no return value to indicate
364 error, but if `sleep' returns SECONDS, it probably didn't work. */
365 extern unsigned int sleep (unsigned int __seconds) __THROW;
367 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
368 /* Set an alarm to go off (generating a SIGALRM signal) in VALUE
369 microseconds. If INTERVAL is nonzero, when the alarm goes off, the
370 timer is reset to go off every INTERVAL microseconds thereafter.
371 Returns the number of microseconds remaining before the alarm. */
372 extern __useconds_t ualarm (__useconds_t __value, __useconds_t __interval)
375 /* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
377 extern int usleep (__useconds_t __useconds) __THROW;
381 /* Suspend the process until a signal arrives.
382 This always returns -1 and sets `errno' to EINTR. */
383 extern int pause (void) __THROW;
386 /* Change the owner and group of FILE. */
387 extern int chown (__const char *__file, __uid_t __owner, __gid_t __group)
390 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
391 /* Change the owner and group of the file that FD is open on. */
392 extern int fchown (int __fd, __uid_t __owner, __gid_t __group) __THROW;
395 /* Change owner and group of FILE, if it is a symbolic
396 link the ownership of the symbolic link is changed. */
397 extern int lchown (__const char *__file, __uid_t __owner, __gid_t __group)
400 #endif /* Use BSD || X/Open Unix. */
402 /* Change the process's working directory to PATH. */
403 extern int chdir (__const char *__path) __THROW;
405 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
406 /* Change the process's working directory to the one FD is open on. */
407 extern int fchdir (int __fd) __THROW;
410 /* Get the pathname of the current working directory,
411 and put it in SIZE bytes of BUF. Returns NULL if the
412 directory couldn't be determined or SIZE was too small.
413 If successful, returns BUF. In GNU, if BUF is NULL,
414 an array is allocated with `malloc'; the array is SIZE
415 bytes long, unless SIZE == 0, in which case it is as
417 extern char *getcwd (char *__buf, size_t __size) __THROW;
419 /* Return a malloc'd string containing the current directory name.
420 If the environment variable `PWD' is set, and its value is correct,
421 that value is used. */
422 extern char *get_current_dir_name (void) __THROW;
426 /* Duplicate FD, returning a new file descriptor on the same file. */
427 extern int dup (int __fd) __THROW;
429 /* Duplicate FD to FD2, closing FD2 and making it open on the same file. */
430 extern int dup2 (int __fd, int __fd2) __THROW;
432 /* NULL-terminated array of "NAME=VALUE" environment variables. */
433 extern char **__environ;
435 extern char **environ;
439 /* Replace the current process, executing PATH with arguments ARGV and
440 environment ENVP. ARGV and ENVP are terminated by NULL pointers. */
441 extern int execve (__const char *__path, char *__const __argv[],
442 char *__const __envp[]) __THROW;
444 /* Execute PATH with arguments ARGV and environment from `environ'. */
445 extern int execv (__const char *__path, char *__const __argv[]) __THROW;
447 /* Execute PATH with all arguments after PATH until a NULL pointer,
448 and the argument after that for environment. */
449 extern int execle (__const char *__path, __const char *__arg, ...) __THROW;
451 /* Execute PATH with all arguments after PATH until
452 a NULL pointer and environment from `environ'. */
453 extern int execl (__const char *__path, __const char *__arg, ...) __THROW;
455 /* Execute FILE, searching in the `PATH' environment variable if it contains
456 no slashes, with arguments ARGV and environment from `environ'. */
457 extern int execvp (__const char *__file, char *__const __argv[]) __THROW;
459 /* Execute FILE, searching in the `PATH' environment variable if
460 it contains no slashes, with all arguments after FILE until a
461 NULL pointer and environment from `environ'. */
462 extern int execlp (__const char *__file, __const char *__arg, ...) __THROW;
465 #if defined __USE_MISC || defined __USE_XOPEN
466 /* Add INC to priority of the current process. */
467 extern int nice (int __inc) __THROW;
471 /* Terminate program execution with the low-order 8 bits of STATUS. */
472 extern void _exit (int __status) __attribute__ ((__noreturn__));
475 /* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
476 the `_SC_*' symbols for the NAME argument to `sysconf';
477 and the `_CS_*' symbols for the NAME argument to `confstr'. */
478 #include <bits/confname.h>
480 /* Get file-specific configuration information about PATH. */
481 extern long int pathconf (__const char *__path, int __name) __THROW;
483 /* Get file-specific configuration about descriptor FD. */
484 extern long int fpathconf (int __fd, int __name) __THROW;
486 /* Get the value of the system variable NAME. */
487 extern long int sysconf (int __name) __THROW __attribute__ ((__const__));
490 /* Get the value of the string-valued system variable NAME. */
491 extern size_t confstr (int __name, char *__buf, size_t __len) __THROW;
495 /* Get the process ID of the calling process. */
496 extern __pid_t getpid (void) __THROW;
498 /* Get the process ID of the calling process's parent. */
499 extern __pid_t getppid (void) __THROW;
501 /* Get the process group ID of the calling process.
502 This function is different on old BSD. */
504 extern __pid_t getpgrp (void) __THROW;
507 extern __pid_t __REDIRECT (getpgrp, (__pid_t __pid) __THROW, __getpgid);
509 # define getpgrp __getpgid
513 /* Get the process group ID of process PID. */
514 extern __pid_t __getpgid (__pid_t __pid) __THROW;
515 #ifdef __USE_XOPEN_EXTENDED
516 extern __pid_t getpgid (__pid_t __pid) __THROW;
520 /* Set the process group ID of the process matching PID to PGID.
521 If PID is zero, the current process's process group ID is set.
522 If PGID is zero, the process ID of the process is used. */
523 extern int setpgid (__pid_t __pid, __pid_t __pgid) __THROW;
525 #if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED
526 /* Both System V and BSD have `setpgrp' functions, but with different
527 calling conventions. The BSD function is the same as POSIX.1 `setpgid'
528 (above). The System V function takes no arguments and puts the calling
529 process in its on group like `setpgid (0, 0)'.
531 New programs should always use `setpgid' instead.
533 The default in GNU is to provide the System V function. The BSD
534 function is available under -D_BSD_SOURCE. */
538 /* Set the process group ID of the calling process to its own PID.
539 This is exactly the same as `setpgid (0, 0)'. */
540 extern int setpgrp (void) __THROW;
544 /* Another name for `setpgid' (above). */
546 extern int __REDIRECT (setpgrp, (__pid_t __pid, __pid_t __pgrp) __THROW,
549 # define setpgrp setpgid
552 # endif /* Favor BSD. */
553 #endif /* Use SVID or BSD. */
555 /* Create a new session with the calling process as its leader.
556 The process group IDs of the session and the calling process
557 are set to the process ID of the calling process, which is returned. */
558 extern __pid_t setsid (void) __THROW;
560 #ifdef __USE_XOPEN_EXTENDED
561 /* Return the session ID of the given process. */
562 extern __pid_t getsid (__pid_t __pid) __THROW;
565 /* Get the real user ID of the calling process. */
566 extern __uid_t getuid (void) __THROW;
568 /* Get the effective user ID of the calling process. */
569 extern __uid_t geteuid (void) __THROW;
571 /* Get the real group ID of the calling process. */
572 extern __gid_t getgid (void) __THROW;
574 /* Get the effective group ID of the calling process. */
575 extern __gid_t getegid (void) __THROW;
577 /* If SIZE is zero, return the number of supplementary groups
578 the calling process is in. Otherwise, fill in the group IDs
579 of its supplementary groups in LIST and return the number written. */
580 extern int getgroups (int __size, __gid_t __list[]) __THROW;
582 /* Set the user ID of the calling process to UID.
583 If the calling process is the super-user, set the real
584 and effective user IDs, and the saved set-user-ID to UID;
585 if not, the effective user ID is set to UID. */
586 extern int setuid (__uid_t __uid) __THROW;
588 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
589 /* Set the real user ID of the calling process to RUID,
590 and the effective user ID of the calling process to EUID. */
591 extern int setreuid (__uid_t __ruid, __uid_t __euid) __THROW;
594 #if defined __USE_BSD || defined __USE_XOPEN2K
595 /* Set the effective user ID of the calling process to UID. */
596 extern int seteuid (__uid_t __uid) __THROW;
597 #endif /* Use BSD. */
599 /* Set the group ID of the calling process to GID.
600 If the calling process is the super-user, set the real
601 and effective group IDs, and the saved set-group-ID to GID;
602 if not, the effective group ID is set to GID. */
603 extern int setgid (__gid_t __gid) __THROW;
605 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
606 /* Set the real group ID of the calling process to RGID,
607 and the effective group ID of the calling process to EGID. */
608 extern int setregid (__gid_t __rgid, __gid_t __egid) __THROW;
611 #if defined __USE_BSD || defined __USE_XOPEN2K
612 /* Set the effective group ID of the calling process to GID. */
613 extern int setegid (__gid_t __gid) __THROW;
614 #endif /* Use BSD. */
617 /* Fetch the effective user ID, real user ID, and saved-set user ID,
618 of the calling process. */
619 extern int getresuid (__uid_t *__euid, __uid_t *__ruid, __uid_t *__suid);
621 /* Fetch the effective group ID, real group ID, and saved-set group ID,
622 of the calling process. */
623 extern int getresgid (__gid_t *__egid, __gid_t *__rgid, __gid_t *__sgid);
625 /* Set the effective user ID, real user ID, and saved-set user ID,
626 of the calling process to EUID, RUID, and SUID, respectively. */
627 extern int setresuid (__uid_t __euid, __uid_t __ruid, __uid_t __suid);
629 /* Set the effective group ID, real group ID, and saved-set group ID,
630 of the calling process to EGID, RGID, and SGID, respectively. */
631 extern int setresgid (__gid_t __egid, __gid_t __rgid, __gid_t __sgid);
635 #ifdef __ARCH_HAS_MMU__
636 /* Clone the calling process, creating an exact copy.
637 Return -1 for errors, 0 to the new process,
638 and the process ID of the new process to the old process. */
639 extern __pid_t fork (void) __THROW;
642 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
643 /* Clone the calling process, but without copying the whole address space.
644 The calling process is suspended until the new process exits or is
645 replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
646 and the process ID of the new process to the old process. */
647 extern __pid_t vfork (void) __THROW;
648 #endif /* Use BSD. */
651 /* Return the pathname of the terminal FD is open on, or NULL on errors.
652 The returned storage is good only until the next call to this function. */
653 extern char *ttyname (int __fd) __THROW;
655 /* Store at most BUFLEN characters of the pathname of the terminal FD is
656 open on in BUF. Return 0 on success, otherwise an error number. */
657 extern int ttyname_r (int __fd, char *__buf, size_t __buflen) __THROW;
659 /* Return 1 if FD is a valid descriptor associated
660 with a terminal, zero if not. */
661 extern int isatty (int __fd) __THROW;
665 /* Make a link to FROM named TO. */
666 extern int link (__const char *__from, __const char *__to) __THROW;
668 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
669 /* Make a symbolic link to FROM named TO. */
670 extern int symlink (__const char *__from, __const char *__to) __THROW;
672 /* Read the contents of the symbolic link PATH into no more than
673 LEN bytes of BUF. The contents are not null-terminated.
674 Returns the number of characters read, or -1 for errors. */
675 extern int readlink (__const char *__restrict __path, char *__restrict __buf,
676 size_t __len) __THROW;
677 #endif /* Use BSD. */
679 /* Remove the link NAME. */
680 extern int unlink (__const char *__name) __THROW;
682 /* Remove the directory PATH. */
683 extern int rmdir (__const char *__path) __THROW;
686 /* Return the foreground process group ID of FD. */
687 extern __pid_t tcgetpgrp (int __fd) __THROW;
689 /* Set the foreground process group ID of FD set PGRP_ID. */
690 extern int tcsetpgrp (int __fd, __pid_t __pgrp_id) __THROW;
693 /* Return the login name of the user. */
694 extern char *getlogin (void) __THROW;
695 #if defined __USE_REENTRANT || defined __USE_UNIX98
696 /* Return at most NAME_LEN characters of the login name of the user in NAME.
697 If it cannot be determined or some other error occurred, return the error
698 code. Otherwise return 0. */
699 extern int getlogin_r (char *__name, size_t __name_len) __THROW;
705 /* Get definitions and prototypes for functions to process the
706 arguments in ARGV (ARGC of them, minus the program name) for
707 options given in OPTS. */
708 # define __need_getopt
709 # include <bits/getopt.h>
713 #if defined __USE_BSD || defined __USE_UNIX98
714 /* Put the name of the current host in no more than LEN bytes of NAME.
715 The result is null-terminated if LEN is large enough for the full
716 name and the terminator. */
717 extern int gethostname (char *__name, size_t __len) __THROW;
721 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_UNIX98)
722 /* Set the name of the current host to NAME, which is LEN bytes long.
723 This call is restricted to the super-user. */
724 extern int sethostname (__const char *__name, size_t __len) __THROW;
726 /* Set the current machine's Internet number to ID.
727 This call is restricted to the super-user. */
728 extern int sethostid (long int __id) __THROW;
731 /* Get and set the NIS (aka YP) domain name, if any.
732 Called just like `gethostname' and `sethostname'.
733 The NIS domain name is usually the empty string when not using NIS. */
734 extern int getdomainname (char *__name, size_t __len) __THROW;
735 extern int setdomainname (__const char *__name, size_t __len) __THROW;
738 /* Revoke access permissions to all processes currently communicating
739 with the control terminal, and then send a SIGHUP signal to the process
740 group of the control terminal. */
741 extern int vhangup (void) __THROW;
745 /* Turn accounting on if NAME is an existing file. The system will then write
746 a record for each process as it terminates, to this file. If NAME is NULL,
747 turn accounting off. This call is restricted to the super-user. */
748 extern int acct (__const char *__name) __THROW;
751 /* Successive calls return the shells listed in `/etc/shells'. */
752 extern char *getusershell (void) __THROW;
753 extern void endusershell (void) __THROW; /* Discard cached info. */
754 extern void setusershell (void) __THROW; /* Rewind and re-read the file. */
757 #if defined __ARCH_HAS_MMU__
758 /* Put the program in the background, and dissociate from the controlling
759 terminal. If NOCHDIR is zero, do `chdir ("/")'. If NOCLOSE is zero,
760 redirects stdin, stdout, and stderr to /dev/null. */
761 extern int daemon (int __nochdir, int __noclose) __THROW;
763 #endif /* Use BSD || X/Open. */
766 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
767 /* Make PATH be the root directory (the starting point for absolute paths).
768 This call is restricted to the super-user. */
769 extern int chroot (__const char *__path) __THROW;
771 /* Prompt with PROMPT and read a string from the terminal without echoing.
772 Uses /dev/tty if possible; otherwise stderr and stdin. */
773 extern char *getpass (__const char *__prompt) __THROW;
774 #endif /* Use BSD || X/Open. */
777 #if defined __USE_BSD || defined __USE_XOPEN
778 /* Make all changes done to FD actually appear on disk. */
779 extern int fsync (int __fd) __THROW;
780 #endif /* Use BSD || X/Open. */
783 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
785 /* Return the current machine's Internet number. */
786 extern long int gethostid (void) __THROW;
788 /* Make all changes done to all files actually appear on disk. */
789 extern void sync (void) __THROW;
792 /* Return the number of bytes in a page. This is the system's page size,
793 which is not necessarily the same as the hardware page size. */
794 extern int getpagesize (void) __THROW __attribute__ ((__const__));
797 /* Truncate FILE to LENGTH bytes. */
798 # ifndef __USE_FILE_OFFSET64
799 extern int truncate (__const char *__file, __off_t __length) __THROW;
802 extern int __REDIRECT (truncate,
803 (__const char *__file, __off64_t __length) __THROW,
806 # define truncate truncate64
809 # ifdef __USE_LARGEFILE64
810 extern int truncate64 (__const char *__file, __off64_t __length) __THROW;
813 /* Truncate the file FD is open on to LENGTH bytes. */
814 # ifndef __USE_FILE_OFFSET64
815 extern int ftruncate (int __fd, __off_t __length) __THROW;
818 extern int __REDIRECT (ftruncate, (int __fd, __off64_t __length) __THROW,
821 # define ftruncate ftruncate64
824 # ifdef __USE_LARGEFILE64
825 extern int ftruncate64 (int __fd, __off64_t __length) __THROW;
829 /* Return the maximum number of file descriptors
830 the current process could possibly have. */
831 extern int getdtablesize (void) __THROW;
833 #endif /* Use BSD || X/Open Unix. */
836 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
838 /* Set the end of accessible data space (aka "the break") to ADDR.
839 Returns zero on success and -1 for errors (with errno set). */
840 extern int brk (void *__addr) __THROW;
842 /* Increase or decrease the end of accessible data space by DELTA bytes.
843 If successful, returns the address the previous end of data space
844 (i.e. the beginning of the new space, if DELTA > 0);
845 returns (void *) -1 for errors (with errno set). */
846 extern void *sbrk (intptr_t __delta) __THROW;
851 /* Invoke `system call' number SYSNO, passing it the remaining arguments.
852 This is completely system-dependent, and not often useful.
854 In Unix, `syscall' sets `errno' for all errors and most calls return -1
855 for errors; in many systems you cannot pass arguments or get return
856 values for all system calls (`pipe', `fork', and `getppid' typically
859 In Mach, all system calls take normal arguments and always return an
860 error code (zero for success). */
861 extern long int syscall (long int __sysno, ...) __THROW;
863 #endif /* Use misc. */
866 #if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
867 /* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
868 files consistent. Some systems have them there and some here, and some
869 software depends on the macros being defined without including both. */
871 /* `lockf' is a simpler interface to the locking facilities of `fcntl'.
872 LEN is always relative to the current file position.
873 The CMD argument is one of the following. */
875 # define F_ULOCK 0 /* Unlock a previously locked region. */
876 # define F_LOCK 1 /* Lock a region for exclusive use. */
877 # define F_TLOCK 2 /* Test and lock a region for exclusive use. */
878 # define F_TEST 3 /* Test a region for other processes locks. */
880 # ifndef __USE_FILE_OFFSET64
881 extern int lockf (int __fd, int __cmd, __off_t __len) __THROW;
884 extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len) __THROW,
887 # define lockf lockf64
890 # ifdef __USE_LARGEFILE64
891 extern int lockf64 (int __fd, int __cmd, __off64_t __len) __THROW;
893 #endif /* Use misc and F_LOCK not already defined. */
898 /* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
901 # define TEMP_FAILURE_RETRY(expression) \
903 ({ long int __result; \
904 do __result = (long int) (expression); \
905 while (__result == -1L && errno == EINTR); \
909 #if defined __USE_POSIX199309 || defined __USE_UNIX98
910 /* Synchronize at least the data part of a file with the underlying
912 extern int fdatasync (int __fildes) __THROW;
913 #endif /* Use POSIX199309 */
916 /* XPG4.2 specifies that prototypes for the encryption functions must
919 /* Encrypt at most 8 characters from KEY using salt to perturb DES. */
920 extern char *crypt (__const char *__key, __const char *__salt) __THROW;
922 /* Encrypt data in BLOCK in place if EDFLAG is zero; otherwise decrypt
924 extern void encrypt (char *__block, int __edflag) __THROW;
927 /* Swab pairs bytes in the first N bytes of the area pointed to by
928 FROM and copy the result to TO. The value of TO must not be in the
929 range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
930 is without partner. */
931 extern void swab (__const void *__restrict __from, void *__restrict __to,
932 ssize_t __n) __THROW;
936 /* The Single Unix specification demands this prototype to be here.
937 It is also found in <stdio.h>. */
939 /* Return the name of the controlling terminal. */
940 extern char *ctermid (char *__s) __THROW;
945 #endif /* unistd.h */