1 /* Copyright (C) 1991-2002, 2003 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 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. */
60 # define _XOPEN_VERSION 500
62 # define _XOPEN_VERSION 4
65 /* Commands and utilities from XPG4 are available. */
66 #define _XOPEN_XCU_VERSION 4
68 /* We are compatible with the old published standards as well. */
73 /* The X/Open Unix extensions are available. */
76 /* Encryption is present. */
77 #define _XOPEN_CRYPT 1
79 /* The enhanced internationalization capabilities according to XPG4.2
81 #define _XOPEN_ENH_I18N 1
83 /* The legacy interfaces are also available. */
84 #define _XOPEN_LEGACY 1
87 /* Get values of POSIX options:
89 If these symbols are defined, the corresponding features are
90 always available. If not, they may be available sometimes.
91 The current values can be obtained with `sysconf'.
93 _POSIX_JOB_CONTROL Job control is supported.
94 _POSIX_SAVED_IDS Processes have a saved set-user-ID
95 and a saved set-group-ID.
96 _POSIX_REALTIME_SIGNALS Real-time, queued signals are supported.
97 _POSIX_PRIORITY_SCHEDULING Priority scheduling is supported.
98 _POSIX_TIMERS POSIX.4 clocks and timers are supported.
99 _POSIX_ASYNCHRONOUS_IO Asynchronous I/O is supported.
100 _POSIX_PRIORITIZED_IO Prioritized asynchronous I/O is supported.
101 _POSIX_SYNCHRONIZED_IO Synchronizing file data is supported.
102 _POSIX_FSYNC The fsync function is present.
103 _POSIX_MAPPED_FILES Mapping of files to memory is supported.
104 _POSIX_MEMLOCK Locking of all memory is supported.
105 _POSIX_MEMLOCK_RANGE Locking of ranges of memory is supported.
106 _POSIX_MEMORY_PROTECTION Setting of memory protections is supported.
107 _POSIX_MESSAGE_PASSING POSIX.4 message queues are supported.
108 _POSIX_SEMAPHORES POSIX.4 counting semaphores are supported.
109 _POSIX_SHARED_MEMORY_OBJECTS POSIX.4 shared memory objects are supported.
110 _POSIX_THREADS POSIX.1c pthreads are supported.
111 _POSIX_THREAD_ATTR_STACKADDR Thread stack address attribute option supported.
112 _POSIX_THREAD_ATTR_STACKSIZE Thread stack size attribute option supported.
113 _POSIX_THREAD_SAFE_FUNCTIONS Thread-safe functions are supported.
114 _POSIX_THREAD_PRIORITY_SCHEDULING
115 POSIX.1c thread execution scheduling supported.
116 _POSIX_THREAD_PRIO_INHERIT Thread priority inheritance option supported.
117 _POSIX_THREAD_PRIO_PROTECT Thread priority protection option supported.
118 _POSIX_THREAD_PROCESS_SHARED Process-shared synchronization supported.
119 _POSIX_PII Protocol-independent interfaces are supported.
120 _POSIX_PII_XTI XTI protocol-indep. interfaces are supported.
121 _POSIX_PII_SOCKET Socket protocol-indep. interfaces are supported.
122 _POSIX_PII_INTERNET Internet family of protocols supported.
123 _POSIX_PII_INTERNET_STREAM Connection-mode Internet protocol supported.
124 _POSIX_PII_INTERNET_DGRAM Connectionless Internet protocol supported.
125 _POSIX_PII_OSI ISO/OSI family of protocols supported.
126 _POSIX_PII_OSI_COTS Connection-mode ISO/OSI service supported.
127 _POSIX_PII_OSI_CLTS Connectionless ISO/OSI service supported.
128 _POSIX_POLL Implementation supports `poll' function.
129 _POSIX_SELECT Implementation supports `select' and `pselect'.
131 _XOPEN_REALTIME X/Open realtime support is available.
132 _XOPEN_REALTIME_THREADS X/Open realtime thread support is available.
133 _XOPEN_SHM Shared memory interface according to XPG4.2.
135 _XBS5_ILP32_OFF32 Implementation provides environment with 32-bit
136 int, long, pointer, and off_t types.
137 _XBS5_ILP32_OFFBIG Implementation provides environment with 32-bit
138 int, long, and pointer and off_t with at least
140 _XBS5_LP64_OFF64 Implementation provides environment with 32-bit
141 int, and 64-bit long, pointer, and off_t types.
142 _XBS5_LPBIG_OFFBIG Implementation provides environment with at
143 least 32 bits int and long, pointer, and off_t
144 with at least 64 bits.
146 If any of these symbols is defined as -1, the corresponding option is not
147 true for any file. If any is defined as other than -1, the corresponding
148 option is true for all files. If a symbol is not defined at all, the value
149 for a specific file can be obtained from `pathconf' and `fpathconf'.
151 _POSIX_CHOWN_RESTRICTED Only the super user can use `chown' to change
152 the owner of a file. `chown' can only be used
153 to change the group ID of a file to a group of
154 which the calling process is a member.
155 _POSIX_NO_TRUNC Pathname components longer than
156 NAME_MAX generate an error.
157 _POSIX_VDISABLE If defined, if the value of an element of the
158 `c_cc' member of `struct termios' is
159 _POSIX_VDISABLE, no character will have the
160 effect associated with that element.
161 _POSIX_SYNC_IO Synchronous I/O may be performed.
162 _POSIX_ASYNC_IO Asynchronous I/O may be performed.
163 _POSIX_PRIO_IO Prioritized Asynchronous I/O may be performed.
165 Support for the Large File Support interface is not generally available.
166 If it is available the following constants are defined to one.
167 _LFS64_LARGEFILE Low-level I/O supports large files.
168 _LFS64_STDIO Standard I/O supports large files.
171 #include <bits/posix_opt.h>
173 /* Get the environment definitions from Unix98. */
175 # include <bits/environments.h>
178 /* Standard file descriptors. */
179 #define STDIN_FILENO 0 /* Standard input. */
180 #define STDOUT_FILENO 1 /* Standard output. */
181 #define STDERR_FILENO 2 /* Standard error output. */
184 /* All functions that are not declared anywhere else. */
186 #include <bits/types.h>
188 #ifndef __ssize_t_defined
189 typedef __ssize_t ssize_t
;
190 # define __ssize_t_defined
193 #define __need_size_t
198 /* The Single Unix specification says that some more types are
200 # ifndef __gid_t_defined
201 typedef __gid_t gid_t
;
202 # define __gid_t_defined
205 # ifndef __uid_t_defined
206 typedef __uid_t uid_t
;
207 # define __uid_t_defined
210 # ifndef __off_t_defined
211 # ifndef __USE_FILE_OFFSET64
212 typedef __off_t off_t
;
214 typedef __off64_t off_t
;
216 # define __off_t_defined
218 # if defined __USE_LARGEFILE64 && !defined __off64_t_defined
219 typedef __off64_t off64_t
;
220 # define __off64_t_defined
223 # ifndef __useconds_t_defined
224 typedef __useconds_t useconds_t
;
225 # define __useconds_t_defined
228 # ifndef __pid_t_defined
229 typedef __pid_t pid_t
;
230 # define __pid_t_defined
234 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
235 # ifndef __intptr_t_defined
236 typedef __intptr_t
intptr_t;
237 # define __intptr_t_defined
241 #if defined __USE_BSD || defined __USE_XOPEN
242 # ifndef __socklen_t_defined
243 typedef __socklen_t socklen_t
;
244 # define __socklen_t_defined
248 /* Values for the second argument to access.
249 These may be OR'd together. */
250 #define R_OK 4 /* Test for read permission. */
251 #define W_OK 2 /* Test for write permission. */
252 #define X_OK 1 /* Test for execute permission. */
253 #define F_OK 0 /* Test for existence. */
255 /* Test for access to NAME using the real UID and real GID. */
256 extern int access (__const
char *__name
, int __type
) __THROW
;
259 /* Test for access to NAME using the effective UID and GID
260 (as normal file operations use). */
261 extern int euidaccess (__const
char *__name
, int __type
) __THROW
;
265 /* Values for the WHENCE argument to lseek. */
266 #ifndef _STDIO_H /* <stdio.h> has the same definitions. */
267 # define SEEK_SET 0 /* Seek from beginning of file. */
268 # define SEEK_CUR 1 /* Seek from current position. */
269 # define SEEK_END 2 /* Seek from end of file. */
272 #if defined __USE_BSD && !defined L_SET
273 /* Old BSD names for the same constants; just for compatibility. */
274 # define L_SET SEEK_SET
275 # define L_INCR SEEK_CUR
276 # define L_XTND SEEK_END
280 /* Move FD's file position to OFFSET bytes from the
281 beginning of the file (if WHENCE is SEEK_SET),
282 the current position (if WHENCE is SEEK_CUR),
283 or the end of the file (if WHENCE is SEEK_END).
284 Return the new file position. */
285 #ifndef __USE_FILE_OFFSET64
286 extern __off_t
lseek (int __fd
, __off_t __offset
, int __whence
) __THROW
;
289 extern __off64_t
__REDIRECT (lseek
,
290 (int __fd
, __off64_t __offset
, int __whence
)
294 # define lseek lseek64
297 #ifdef __USE_LARGEFILE64
298 extern __off64_t
lseek64 (int __fd
, __off64_t __offset
, int __whence
) __THROW
;
301 /* Close the file descriptor FD.
303 This function is a cancellation point and therefore not marked with
305 extern int close (int __fd
);
307 /* Read NBYTES into BUF from FD. Return the
308 number read, -1 for errors or 0 for EOF.
310 This function is a cancellation point and therefore not marked with
312 extern ssize_t
read (int __fd
, void *__buf
, size_t __nbytes
);
314 /* Write N bytes of BUF to FD. Return the number written, or -1.
316 This function is a cancellation point and therefore not marked with
318 extern ssize_t
write (int __fd
, __const
void *__buf
, size_t __n
);
321 # ifndef __USE_FILE_OFFSET64
322 /* Read NBYTES into BUF from FD at the given position OFFSET without
323 changing the file pointer. Return the number read, -1 for errors
326 This function is a cancellation point and therefore not marked with
328 extern ssize_t
pread (int __fd
, void *__buf
, size_t __nbytes
,
331 /* Write N bytes of BUF to FD at the given position OFFSET without
332 changing the file pointer. Return the number written, or -1.
334 This function is a cancellation point and therefore not marked with
336 extern ssize_t
pwrite (int __fd
, __const
void *__buf
, size_t __n
,
340 extern ssize_t
__REDIRECT (pread
, (int __fd
, void *__buf
, size_t __nbytes
,
343 extern ssize_t
__REDIRECT (pwrite
, (int __fd
, __const
void *__buf
,
344 size_t __nbytes
, __off64_t __offset
),
347 # define pread pread64
348 # define pwrite pwrite64
352 # ifdef __USE_LARGEFILE64
353 /* Read NBYTES into BUF from FD at the given position OFFSET without
354 changing the file pointer. Return the number read, -1 for errors
356 extern ssize_t
pread64 (int __fd
, void *__buf
, size_t __nbytes
,
358 /* Write N bytes of BUF to FD at the given position OFFSET without
359 changing the file pointer. Return the number written, or -1. */
360 extern ssize_t
pwrite64 (int __fd
, __const
void *__buf
, size_t __n
,
365 /* Create a one-way communication channel (pipe).
366 If successful, two file descriptors are stored in PIPEDES;
367 bytes written on PIPEDES[1] can be read from PIPEDES[0].
368 Returns 0 if successful, -1 if not. */
369 extern int pipe (int __pipedes
[2]) __THROW
;
371 /* Schedule an alarm. In SECONDS seconds, the process will get a SIGALRM.
372 If SECONDS is zero, any currently scheduled alarm will be cancelled.
373 The function returns the number of seconds remaining until the last
374 alarm scheduled would have signaled, or zero if there wasn't one.
375 There is no return value to indicate an error, but you can set `errno'
376 to 0 and check its value after calling `alarm', and this might tell you.
377 The signal may come late due to processor scheduling. */
378 extern unsigned int alarm (unsigned int __seconds
) __THROW
;
380 /* Make the process sleep for SECONDS seconds, or until a signal arrives
381 and is not ignored. The function returns the number of seconds less
382 than SECONDS which it actually slept (thus zero if it slept the full time).
383 If a signal handler does a `longjmp' or modifies the handling of the
384 SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
385 signal afterwards is undefined. There is no return value to indicate
386 error, but if `sleep' returns SECONDS, it probably didn't work.
388 This function is a cancellation point and therefore not marked with
390 extern unsigned int sleep (unsigned int __seconds
);
392 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
393 /* Set an alarm to go off (generating a SIGALRM signal) in VALUE
394 microseconds. If INTERVAL is nonzero, when the alarm goes off, the
395 timer is reset to go off every INTERVAL microseconds thereafter.
396 Returns the number of microseconds remaining before the alarm. */
397 extern __useconds_t
ualarm (__useconds_t __value
, __useconds_t __interval
)
400 /* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
403 This function is a cancellation point and therefore not marked with
405 extern int usleep (__useconds_t __useconds
);
409 /* Suspend the process until a signal arrives.
410 This always returns -1 and sets `errno' to EINTR.
412 This function is a cancellation point and therefore not marked with
414 extern int pause (void);
417 /* Change the owner and group of FILE. */
418 extern int chown (__const
char *__file
, __uid_t __owner
, __gid_t __group
)
421 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
422 /* Change the owner and group of the file that FD is open on. */
423 extern int fchown (int __fd
, __uid_t __owner
, __gid_t __group
) __THROW
;
426 /* Change owner and group of FILE, if it is a symbolic
427 link the ownership of the symbolic link is changed. */
428 extern int lchown (__const
char *__file
, __uid_t __owner
, __gid_t __group
)
431 #endif /* Use BSD || X/Open Unix. */
433 /* Change the process's working directory to PATH. */
434 extern int chdir (__const
char *__path
) __THROW
;
436 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
437 /* Change the process's working directory to the one FD is open on. */
438 extern int fchdir (int __fd
) __THROW
;
441 /* Get the pathname of the current working directory,
442 and put it in SIZE bytes of BUF. Returns NULL if the
443 directory couldn't be determined or SIZE was too small.
444 If successful, returns BUF. In GNU, if BUF is NULL,
445 an array is allocated with `malloc'; the array is SIZE
446 bytes long, unless SIZE == 0, in which case it is as
448 extern char *getcwd (char *__buf
, size_t __size
) __THROW
;
451 /* Return a malloc'd string containing the current directory name.
452 If the environment variable `PWD' is set, and its value is correct,
453 that value is used. */
454 extern char *get_current_dir_name (void) __THROW
;
457 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
458 /* Put the absolute pathname of the current working directory in BUF.
459 If successful, return BUF. If not, put an error message in
460 BUF and return NULL. BUF should be at least PATH_MAX bytes long. */
461 extern char *getwd (char *__buf
) __THROW
;
465 /* Duplicate FD, returning a new file descriptor on the same file. */
466 extern int dup (int __fd
) __THROW
;
468 /* Duplicate FD to FD2, closing FD2 and making it open on the same file. */
469 extern int dup2 (int __fd
, int __fd2
) __THROW
;
471 /* NULL-terminated array of "NAME=VALUE" environment variables. */
472 extern char **__environ
;
474 extern char **environ
;
478 /* Replace the current process, executing PATH with arguments ARGV and
479 environment ENVP. ARGV and ENVP are terminated by NULL pointers. */
480 extern int execve (__const
char *__path
, char *__const __argv
[],
481 char *__const __envp
[]) __THROW
;
484 /* Execute the file FD refers to, overlaying the running program image.
485 ARGV and ENVP are passed to the new program, as for `execve'. */
486 extern int fexecve (int __fd
, char *__const __argv
[], char *__const __envp
[])
491 /* Execute PATH with arguments ARGV and environment from `environ'. */
492 extern int execv (__const
char *__path
, char *__const __argv
[]) __THROW
;
494 /* Execute PATH with all arguments after PATH until a NULL pointer,
495 and the argument after that for environment. */
496 extern int execle (__const
char *__path
, __const
char *__arg
, ...) __THROW
;
498 /* Execute PATH with all arguments after PATH until
499 a NULL pointer and environment from `environ'. */
500 extern int execl (__const
char *__path
, __const
char *__arg
, ...) __THROW
;
502 /* Execute FILE, searching in the `PATH' environment variable if it contains
503 no slashes, with arguments ARGV and environment from `environ'. */
504 extern int execvp (__const
char *__file
, char *__const __argv
[]) __THROW
;
506 /* Execute FILE, searching in the `PATH' environment variable if
507 it contains no slashes, with all arguments after FILE until a
508 NULL pointer and environment from `environ'. */
509 extern int execlp (__const
char *__file
, __const
char *__arg
, ...) __THROW
;
512 #if defined __USE_MISC || defined __USE_XOPEN
513 /* Add INC to priority of the current process. */
514 extern int nice (int __inc
) __THROW
;
518 /* Terminate program execution with the low-order 8 bits of STATUS. */
519 extern void _exit (int __status
) __attribute__ ((__noreturn__
));
522 /* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
523 the `_SC_*' symbols for the NAME argument to `sysconf';
524 and the `_CS_*' symbols for the NAME argument to `confstr'. */
525 #include <bits/confname.h>
527 /* Get file-specific configuration information about PATH. */
528 extern long int pathconf (__const
char *__path
, int __name
) __THROW
;
530 /* Get file-specific configuration about descriptor FD. */
531 extern long int fpathconf (int __fd
, int __name
) __THROW
;
533 /* Get the value of the system variable NAME. */
534 extern long int sysconf (int __name
) __THROW
__attribute__ ((__const__
));
537 /* Get the value of the string-valued system variable NAME. */
538 extern size_t confstr (int __name
, char *__buf
, size_t __len
) __THROW
;
542 /* Get the process ID of the calling process. */
543 extern __pid_t
getpid (void) __THROW
;
545 /* Get the process ID of the calling process's parent. */
546 extern __pid_t
getppid (void) __THROW
;
548 /* Get the process group ID of the calling process.
549 This function is different on old BSD. */
551 extern __pid_t
getpgrp (void) __THROW
;
554 extern __pid_t
__REDIRECT (getpgrp
, (__pid_t __pid
) __THROW
, __getpgid
);
556 # define getpgrp __getpgid
560 /* Get the process group ID of process PID. */
561 extern __pid_t
__getpgid (__pid_t __pid
) __THROW
;
562 #ifdef __USE_XOPEN_EXTENDED
563 extern __pid_t
getpgid (__pid_t __pid
) __THROW
;
567 /* Set the process group ID of the process matching PID to PGID.
568 If PID is zero, the current process's process group ID is set.
569 If PGID is zero, the process ID of the process is used. */
570 extern int setpgid (__pid_t __pid
, __pid_t __pgid
) __THROW
;
572 #if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED
573 /* Both System V and BSD have `setpgrp' functions, but with different
574 calling conventions. The BSD function is the same as POSIX.1 `setpgid'
575 (above). The System V function takes no arguments and puts the calling
576 process in its on group like `setpgid (0, 0)'.
578 New programs should always use `setpgid' instead.
580 The default in GNU is to provide the System V function. The BSD
581 function is available under -D_BSD_SOURCE. */
585 /* Set the process group ID of the calling process to its own PID.
586 This is exactly the same as `setpgid (0, 0)'. */
587 extern int setpgrp (void) __THROW
;
591 /* Another name for `setpgid' (above). */
593 extern int __REDIRECT (setpgrp
, (__pid_t __pid
, __pid_t __pgrp
) __THROW
,
596 # define setpgrp setpgid
599 # endif /* Favor BSD. */
600 #endif /* Use SVID or BSD. */
602 /* Create a new session with the calling process as its leader.
603 The process group IDs of the session and the calling process
604 are set to the process ID of the calling process, which is returned. */
605 extern __pid_t
setsid (void) __THROW
;
607 #ifdef __USE_XOPEN_EXTENDED
608 /* Return the session ID of the given process. */
609 extern __pid_t
getsid (__pid_t __pid
) __THROW
;
612 /* Get the real user ID of the calling process. */
613 extern __uid_t
getuid (void) __THROW
;
615 /* Get the effective user ID of the calling process. */
616 extern __uid_t
geteuid (void) __THROW
;
618 /* Get the real group ID of the calling process. */
619 extern __gid_t
getgid (void) __THROW
;
621 /* Get the effective group ID of the calling process. */
622 extern __gid_t
getegid (void) __THROW
;
624 /* If SIZE is zero, return the number of supplementary groups
625 the calling process is in. Otherwise, fill in the group IDs
626 of its supplementary groups in LIST and return the number written. */
627 extern int getgroups (int __size
, __gid_t __list
[]) __THROW
;
630 /* Return nonzero iff the calling process is in group GID. */
631 extern int group_member (__gid_t __gid
) __THROW
;
634 /* Set the user ID of the calling process to UID.
635 If the calling process is the super-user, set the real
636 and effective user IDs, and the saved set-user-ID to UID;
637 if not, the effective user ID is set to UID. */
638 extern int setuid (__uid_t __uid
) __THROW
;
640 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
641 /* Set the real user ID of the calling process to RUID,
642 and the effective user ID of the calling process to EUID. */
643 extern int setreuid (__uid_t __ruid
, __uid_t __euid
) __THROW
;
646 #if defined __USE_BSD || defined __USE_XOPEN2K
647 /* Set the effective user ID of the calling process to UID. */
648 extern int seteuid (__uid_t __uid
) __THROW
;
649 #endif /* Use BSD. */
651 /* Set the group ID of the calling process to GID.
652 If the calling process is the super-user, set the real
653 and effective group IDs, and the saved set-group-ID to GID;
654 if not, the effective group ID is set to GID. */
655 extern int setgid (__gid_t __gid
) __THROW
;
657 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
658 /* Set the real group ID of the calling process to RGID,
659 and the effective group ID of the calling process to EGID. */
660 extern int setregid (__gid_t __rgid
, __gid_t __egid
) __THROW
;
663 #if defined __USE_BSD || defined __USE_XOPEN2K
664 /* Set the effective group ID of the calling process to GID. */
665 extern int setegid (__gid_t __gid
) __THROW
;
666 #endif /* Use BSD. */
669 /* Fetch the effective user ID, real user ID, and saved-set user ID,
670 of the calling process. */
671 extern int getresuid (__uid_t
*__euid
, __uid_t
*__ruid
, __uid_t
*__suid
);
673 /* Fetch the effective group ID, real group ID, and saved-set group ID,
674 of the calling process. */
675 extern int getresgid (__gid_t
*__egid
, __gid_t
*__rgid
, __gid_t
*__sgid
);
677 /* Set the effective user ID, real user ID, and saved-set user ID,
678 of the calling process to EUID, RUID, and SUID, respectively. */
679 extern int setresuid (__uid_t __euid
, __uid_t __ruid
, __uid_t __suid
);
681 /* Set the effective group ID, real group ID, and saved-set group ID,
682 of the calling process to EGID, RGID, and SGID, respectively. */
683 extern int setresgid (__gid_t __egid
, __gid_t __rgid
, __gid_t __sgid
);
687 /* Clone the calling process, creating an exact copy.
688 Return -1 for errors, 0 to the new process,
689 and the process ID of the new process to the old process. */
690 extern __pid_t
fork (void) __THROW
;
692 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
693 /* Clone the calling process, but without copying the whole address space.
694 The calling process is suspended until the new process exits or is
695 replaced by a call to `execve'. Return -1 for errors, 0 to the new process,
696 and the process ID of the new process to the old process. */
697 extern __pid_t
vfork (void) __THROW
;
698 #endif /* Use BSD. */
701 /* Return the pathname of the terminal FD is open on, or NULL on errors.
702 The returned storage is good only until the next call to this function.
704 This function is a possible cancellation points and therefore not
705 marked with __THROW. */
706 extern char *ttyname (int __fd
);
708 /* Store at most BUFLEN characters of the pathname of the terminal FD is
709 open on in BUF. Return 0 on success, otherwise an error number.
711 This function is a possible cancellation points and therefore not
712 marked with __THROW. */
713 extern int ttyname_r (int __fd
, char *__buf
, size_t __buflen
);
715 /* Return 1 if FD is a valid descriptor associated
716 with a terminal, zero if not. */
717 extern int isatty (int __fd
) __THROW
;
719 #if defined __USE_BSD \
720 || (defined __USE_XOPEN_EXTENDED && !defined __USE_UNIX98)
721 /* Return the index into the active-logins file (utmp) for
722 the controlling terminal. */
723 extern int ttyslot (void) __THROW
;
727 /* Make a link to FROM named TO. */
728 extern int link (__const
char *__from
, __const
char *__to
) __THROW
;
730 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
731 /* Make a symbolic link to FROM named TO. */
732 extern int symlink (__const
char *__from
, __const
char *__to
) __THROW
;
734 /* Read the contents of the symbolic link PATH into no more than
735 LEN bytes of BUF. The contents are not null-terminated.
736 Returns the number of characters read, or -1 for errors. */
737 extern int readlink (__const
char *__restrict __path
, char *__restrict __buf
,
738 size_t __len
) __THROW
;
739 #endif /* Use BSD. */
741 /* Remove the link NAME. */
742 extern int unlink (__const
char *__name
) __THROW
;
744 /* Remove the directory PATH. */
745 extern int rmdir (__const
char *__path
) __THROW
;
748 /* Return the foreground process group ID of FD. */
749 extern __pid_t
tcgetpgrp (int __fd
) __THROW
;
751 /* Set the foreground process group ID of FD set PGRP_ID. */
752 extern int tcsetpgrp (int __fd
, __pid_t __pgrp_id
) __THROW
;
755 /* Return the login name of the user.
757 This function is a possible cancellation points and therefore not
758 marked with __THROW. */
759 extern char *getlogin (void);
760 #if defined __USE_REENTRANT || defined __USE_UNIX98
761 /* Return at most NAME_LEN characters of the login name of the user in NAME.
762 If it cannot be determined or some other error occurred, return the error
763 code. Otherwise return 0.
765 This function is a possible cancellation points and therefore not
766 marked with __THROW. */
767 extern int getlogin_r (char *__name
, size_t __name_len
);
771 /* Set the login name returned by `getlogin'. */
772 extern int setlogin (__const
char *__name
) __THROW
;
777 /* Get definitions and prototypes for functions to process the
778 arguments in ARGV (ARGC of them, minus the program name) for
779 options given in OPTS. */
780 # define __need_getopt
785 #if defined __USE_BSD || defined __USE_UNIX98
786 /* Put the name of the current host in no more than LEN bytes of NAME.
787 The result is null-terminated if LEN is large enough for the full
788 name and the terminator. */
789 extern int gethostname (char *__name
, size_t __len
) __THROW
;
793 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_UNIX98)
794 /* Set the name of the current host to NAME, which is LEN bytes long.
795 This call is restricted to the super-user. */
796 extern int sethostname (__const
char *__name
, size_t __len
) __THROW
;
798 /* Set the current machine's Internet number to ID.
799 This call is restricted to the super-user. */
800 extern int sethostid (long int __id
) __THROW
;
803 /* Get and set the NIS (aka YP) domain name, if any.
804 Called just like `gethostname' and `sethostname'.
805 The NIS domain name is usually the empty string when not using NIS. */
806 extern int getdomainname (char *__name
, size_t __len
) __THROW
;
807 extern int setdomainname (__const
char *__name
, size_t __len
) __THROW
;
810 /* Revoke access permissions to all processes currently communicating
811 with the control terminal, and then send a SIGHUP signal to the process
812 group of the control terminal. */
813 extern int vhangup (void) __THROW
;
815 /* Revoke the access of all descriptors currently open on FILE. */
816 extern int revoke (__const
char *__file
) __THROW
;
819 /* Enable statistical profiling, writing samples of the PC into at most
820 SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
821 is enabled, the system examines the user PC and increments
822 SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536]. If SCALE is zero,
823 disable profiling. Returns zero on success, -1 on error. */
824 extern int profil (unsigned short int *__sample_buffer
, size_t __size
,
825 size_t __offset
, unsigned int __scale
) __THROW
;
828 /* Turn accounting on if NAME is an existing file. The system will then write
829 a record for each process as it terminates, to this file. If NAME is NULL,
830 turn accounting off. This call is restricted to the super-user. */
831 extern int acct (__const
char *__name
) __THROW
;
834 /* Successive calls return the shells listed in `/etc/shells'. */
835 extern char *getusershell (void) __THROW
;
836 extern void endusershell (void) __THROW
; /* Discard cached info. */
837 extern void setusershell (void) __THROW
; /* Rewind and re-read the file. */
840 /* Put the program in the background, and dissociate from the controlling
841 terminal. If NOCHDIR is zero, do `chdir ("/")'. If NOCLOSE is zero,
842 redirects stdin, stdout, and stderr to /dev/null. */
843 extern int daemon (int __nochdir
, int __noclose
) __THROW
;
844 #endif /* Use BSD || X/Open. */
847 #if defined __USE_BSD || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
848 /* Make PATH be the root directory (the starting point for absolute paths).
849 This call is restricted to the super-user. */
850 extern int chroot (__const
char *__path
) __THROW
;
852 /* Prompt with PROMPT and read a string from the terminal without echoing.
853 Uses /dev/tty if possible; otherwise stderr and stdin. */
854 extern char *getpass (__const
char *__prompt
) __THROW
;
855 #endif /* Use BSD || X/Open. */
858 #if defined __USE_BSD || defined __USE_XOPEN
859 /* Make all changes done to FD actually appear on disk.
861 This function is a cancellation point and therefore not marked with
863 extern int fsync (int __fd
);
864 #endif /* Use BSD || X/Open. */
867 #if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
869 /* Return the current machine's Internet number. */
870 extern long int gethostid (void) __THROW
;
872 /* Make all changes done to all files actually appear on disk. */
873 extern void sync (void) __THROW
;
876 /* Return the number of bytes in a page. This is the system's page size,
877 which is not necessarily the same as the hardware page size. */
878 extern int getpagesize (void) __THROW
__attribute__ ((__const__
));
881 /* Truncate FILE to LENGTH bytes. */
882 # ifndef __USE_FILE_OFFSET64
883 extern int truncate (__const
char *__file
, __off_t __length
) __THROW
;
886 extern int __REDIRECT (truncate
,
887 (__const
char *__file
, __off64_t __length
) __THROW
,
890 # define truncate truncate64
893 # ifdef __USE_LARGEFILE64
894 extern int truncate64 (__const
char *__file
, __off64_t __length
) __THROW
;
897 /* Truncate the file FD is open on to LENGTH bytes. */
898 # ifndef __USE_FILE_OFFSET64
899 extern int ftruncate (int __fd
, __off_t __length
) __THROW
;
902 extern int __REDIRECT (ftruncate
, (int __fd
, __off64_t __length
) __THROW
,
905 # define ftruncate ftruncate64
908 # ifdef __USE_LARGEFILE64
909 extern int ftruncate64 (int __fd
, __off64_t __length
) __THROW
;
913 /* Return the maximum number of file descriptors
914 the current process could possibly have. */
915 extern int getdtablesize (void) __THROW
;
917 #endif /* Use BSD || X/Open Unix. */
920 #if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
922 /* Set the end of accessible data space (aka "the break") to ADDR.
923 Returns zero on success and -1 for errors (with errno set). */
924 extern int brk (void *__addr
) __THROW
;
926 /* Increase or decrease the end of accessible data space by DELTA bytes.
927 If successful, returns the address the previous end of data space
928 (i.e. the beginning of the new space, if DELTA > 0);
929 returns (void *) -1 for errors (with errno set). */
930 extern void *sbrk (intptr_t __delta
) __THROW
;
935 /* Invoke `system call' number SYSNO, passing it the remaining arguments.
936 This is completely system-dependent, and not often useful.
938 In Unix, `syscall' sets `errno' for all errors and most calls return -1
939 for errors; in many systems you cannot pass arguments or get return
940 values for all system calls (`pipe', `fork', and `getppid' typically
943 In Mach, all system calls take normal arguments and always return an
944 error code (zero for success). */
945 extern long int syscall (long int __sysno
, ...) __THROW
;
947 #endif /* Use misc. */
950 #if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
951 /* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
952 files consistent. Some systems have them there and some here, and some
953 software depends on the macros being defined without including both. */
955 /* `lockf' is a simpler interface to the locking facilities of `fcntl'.
956 LEN is always relative to the current file position.
957 The CMD argument is one of the following.
959 This function is a cancellation point and therefore not marked with
962 # define F_ULOCK 0 /* Unlock a previously locked region. */
963 # define F_LOCK 1 /* Lock a region for exclusive use. */
964 # define F_TLOCK 2 /* Test and lock a region for exclusive use. */
965 # define F_TEST 3 /* Test a region for other processes locks. */
967 # ifndef __USE_FILE_OFFSET64
968 extern int lockf (int __fd
, int __cmd
, __off_t __len
);
971 extern int __REDIRECT (lockf
, (int __fd
, int __cmd
, __off64_t __len
),
974 # define lockf lockf64
977 # ifdef __USE_LARGEFILE64
978 extern int lockf64 (int __fd
, int __cmd
, __off64_t __len
);
980 #endif /* Use misc and F_LOCK not already defined. */
985 /* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
988 # define TEMP_FAILURE_RETRY(expression) \
990 ({ long int __result; \
991 do __result = (long int) (expression); \
992 while (__result == -1L && errno == EINTR); \
996 #if defined __USE_POSIX199309 || defined __USE_UNIX98
997 /* Synchronize at least the data part of a file with the underlying
999 extern int fdatasync (int __fildes
) __THROW
;
1000 #endif /* Use POSIX199309 */
1003 /* XPG4.2 specifies that prototypes for the encryption functions must
1006 /* Encrypt at most 8 characters from KEY using salt to perturb DES. */
1007 extern char *crypt (__const
char *__key
, __const
char *__salt
) __THROW
;
1009 /* Encrypt data in BLOCK in place if EDFLAG is zero; otherwise decrypt
1011 extern void encrypt (char *__block
, int __edflag
) __THROW
;
1014 /* Swab pairs bytes in the first N bytes of the area pointed to by
1015 FROM and copy the result to TO. The value of TO must not be in the
1016 range [FROM - N + 1, FROM - 1]. If N is odd the first byte in FROM
1017 is without partner. */
1018 extern void swab (__const
void *__restrict __from
, void *__restrict __to
,
1019 ssize_t __n
) __THROW
;
1023 /* The Single Unix specification demands this prototype to be here.
1024 It is also found in <stdio.h>. */
1026 /* Return the name of the controlling terminal. */
1027 extern char *ctermid (char *__s
) __THROW
;
1032 #endif /* unistd.h */