2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1991, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * @(#)unistd.h 8.12 (Berkeley) 4/27/95
38 #include <sys/cdefs.h>
39 #include <sys/types.h> /* XXX adds too much pollution. */
40 #include <sys/unistd.h>
41 #include <sys/_null.h>
42 #include <sys/_types.h>
44 #ifndef _GID_T_DECLARED
45 typedef __gid_t gid_t;
46 #define _GID_T_DECLARED
49 #ifndef _OFF_T_DECLARED
50 typedef __off_t off_t;
51 #define _OFF_T_DECLARED
54 #ifndef _PID_T_DECLARED
55 typedef __pid_t pid_t;
56 #define _PID_T_DECLARED
59 #ifndef _SIZE_T_DECLARED
60 typedef __size_t size_t;
61 #define _SIZE_T_DECLARED
64 #ifndef _SSIZE_T_DECLARED
65 typedef __ssize_t ssize_t;
66 #define _SSIZE_T_DECLARED
69 #ifndef _UID_T_DECLARED
70 typedef __uid_t uid_t;
71 #define _UID_T_DECLARED
74 #ifndef _USECONDS_T_DECLARED
75 typedef __useconds_t useconds_t;
76 #define _USECONDS_T_DECLARED
79 #define STDIN_FILENO 0 /* standard input file descriptor */
80 #define STDOUT_FILENO 1 /* standard output file descriptor */
81 #define STDERR_FILENO 2 /* standard error file descriptor */
83 #if __XSI_VISIBLE || __POSIX_VISIBLE >= 200112
84 #define F_ULOCK 0 /* unlock locked section */
85 #define F_LOCK 1 /* lock a section for exclusive use */
86 #define F_TLOCK 2 /* test and lock a section for exclusive use */
87 #define F_TEST 3 /* test a section for locks by other procs */
91 * POSIX options and option groups we unconditionally do or don't
92 * implement. This list includes those options which are exclusively
93 * implemented (or not) in user mode. Please keep this list in
96 * Anything which is defined as zero below **must** have an
97 * implementation for the corresponding sysconf() which is able to
98 * determine conclusively whether or not the feature is supported.
99 * Anything which is defined as other than -1 below **must** have
100 * complete headers, types, and function declarations as specified by
101 * the POSIX standard; however, if the relevant sysconf() function
102 * returns -1, the functions may be stubbed out.
104 #define _POSIX_BARRIERS 200112L
105 #define _POSIX_CPUTIME 200112L
106 #define _POSIX_READER_WRITER_LOCKS 200112L
107 #define _POSIX_REGEXP 1
108 #define _POSIX_SHELL 1
109 #define _POSIX_SPAWN 200112L
110 #define _POSIX_SPIN_LOCKS 200112L
111 #define _POSIX_THREAD_ATTR_STACKADDR 200112L
112 #define _POSIX_THREAD_ATTR_STACKSIZE 200112L
113 #define _POSIX_THREAD_CPUTIME 200112L
114 #define _POSIX_THREAD_PRIO_INHERIT 200112L
115 #define _POSIX_THREAD_PRIO_PROTECT 200112L
116 #define _POSIX_THREAD_PRIORITY_SCHEDULING 200112L
117 #define _POSIX_THREAD_PROCESS_SHARED 200112L
118 #define _POSIX_THREAD_SAFE_FUNCTIONS -1
119 #define _POSIX_THREAD_SPORADIC_SERVER -1
120 #define _POSIX_THREADS 200112L
121 #define _POSIX_TRACE -1
122 #define _POSIX_TRACE_EVENT_FILTER -1
123 #define _POSIX_TRACE_INHERIT -1
124 #define _POSIX_TRACE_LOG -1
125 #define _POSIX2_C_BIND 200112L /* mandatory */
126 #define _POSIX2_C_DEV -1 /* need c99 utility */
127 #define _POSIX2_CHAR_TERM 1
128 #define _POSIX2_FORT_DEV -1 /* need fort77 utility */
129 #define _POSIX2_FORT_RUN 200112L
130 #define _POSIX2_LOCALEDEF -1
131 #define _POSIX2_PBS -1
132 #define _POSIX2_PBS_ACCOUNTING -1
133 #define _POSIX2_PBS_CHECKPOINT -1
134 #define _POSIX2_PBS_LOCATE -1
135 #define _POSIX2_PBS_MESSAGE -1
136 #define _POSIX2_PBS_TRACK -1
137 #define _POSIX2_SW_DEV -1 /* XXX ??? */
138 #define _POSIX2_UPE 200112L
139 #define _V6_ILP32_OFF32 -1
140 #define _V6_ILP32_OFFBIG 0
141 #define _V6_LP64_OFF64 0
142 #define _V6_LPBIG_OFFBIG -1
145 #define _XOPEN_CRYPT -1 /* XXX ??? */
146 #define _XOPEN_ENH_I18N -1 /* mandatory in XSI */
147 #define _XOPEN_LEGACY -1
148 #define _XOPEN_REALTIME -1
149 #define _XOPEN_REALTIME_THREADS -1
150 #define _XOPEN_UNIX -1
153 /* Define the POSIX.2 version we target for compliance. */
154 #define _POSIX2_VERSION 199212L
157 * POSIX-style system configuration variable accessors (for the
158 * sysconf function). The kernel does not directly implement the
159 * sysconf() interface; rather, a C library stub translates references
160 * to sysconf() into calls to sysctl() using a giant switch statement.
161 * Those that are marked `user' are implemented entirely in the C
162 * library and never query the kernel. pathconf() is implemented
163 * directly by the kernel so those are not defined here.
165 #define _SC_ARG_MAX 1
166 #define _SC_CHILD_MAX 2
167 #define _SC_CLK_TCK 3
168 #define _SC_NGROUPS_MAX 4
169 #define _SC_OPEN_MAX 5
170 #define _SC_JOB_CONTROL 6
171 #define _SC_SAVED_IDS 7
172 #define _SC_VERSION 8
173 #define _SC_BC_BASE_MAX 9 /* user */
174 #define _SC_BC_DIM_MAX 10 /* user */
175 #define _SC_BC_SCALE_MAX 11 /* user */
176 #define _SC_BC_STRING_MAX 12 /* user */
177 #define _SC_COLL_WEIGHTS_MAX 13 /* user */
178 #define _SC_EXPR_NEST_MAX 14 /* user */
179 #define _SC_LINE_MAX 15 /* user */
180 #define _SC_RE_DUP_MAX 16 /* user */
181 #define _SC_2_VERSION 17 /* user */
182 #define _SC_2_C_BIND 18 /* user */
183 #define _SC_2_C_DEV 19 /* user */
184 #define _SC_2_CHAR_TERM 20 /* user */
185 #define _SC_2_FORT_DEV 21 /* user */
186 #define _SC_2_FORT_RUN 22 /* user */
187 #define _SC_2_LOCALEDEF 23 /* user */
188 #define _SC_2_SW_DEV 24 /* user */
189 #define _SC_2_UPE 25 /* user */
190 #define _SC_STREAM_MAX 26 /* user */
191 #define _SC_TZNAME_MAX 27 /* user */
193 #if __POSIX_VISIBLE >= 199309
194 #define _SC_ASYNCHRONOUS_IO 28
195 #define _SC_MAPPED_FILES 29
196 #define _SC_MEMLOCK 30
197 #define _SC_MEMLOCK_RANGE 31
198 #define _SC_MEMORY_PROTECTION 32
199 #define _SC_MESSAGE_PASSING 33
200 #define _SC_PRIORITIZED_IO 34
201 #define _SC_PRIORITY_SCHEDULING 35
202 #define _SC_REALTIME_SIGNALS 36
203 #define _SC_SEMAPHORES 37
205 #define _SC_SHARED_MEMORY_OBJECTS 39
206 #define _SC_SYNCHRONIZED_IO 40
207 #define _SC_TIMERS 41
208 #define _SC_AIO_LISTIO_MAX 42
209 #define _SC_AIO_MAX 43
210 #define _SC_AIO_PRIO_DELTA_MAX 44
211 #define _SC_DELAYTIMER_MAX 45
212 #define _SC_MQ_OPEN_MAX 46
213 #define _SC_PAGESIZE 47
214 #define _SC_RTSIG_MAX 48
215 #define _SC_SEM_NSEMS_MAX 49
216 #define _SC_SEM_VALUE_MAX 50
217 #define _SC_SIGQUEUE_MAX 51
218 #define _SC_TIMER_MAX 52
221 #if __POSIX_VISIBLE >= 200112
222 #define _SC_2_PBS 59 /* user */
223 #define _SC_2_PBS_ACCOUNTING 60 /* user */
224 #define _SC_2_PBS_CHECKPOINT 61 /* user */
225 #define _SC_2_PBS_LOCATE 62 /* user */
226 #define _SC_2_PBS_MESSAGE 63 /* user */
227 #define _SC_2_PBS_TRACK 64 /* user */
228 #define _SC_ADVISORY_INFO 65
229 #define _SC_BARRIERS 66 /* user */
230 #define _SC_CLOCK_SELECTION 67
231 #define _SC_CPUTIME 68
232 #define _SC_FILE_LOCKING 69
233 #define _SC_GETGR_R_SIZE_MAX 70 /* user */
234 #define _SC_GETPW_R_SIZE_MAX 71 /* user */
235 #define _SC_HOST_NAME_MAX 72
236 #define _SC_LOGIN_NAME_MAX 73
237 #define _SC_MONOTONIC_CLOCK 74
238 #define _SC_MQ_PRIO_MAX 75
239 #define _SC_READER_WRITER_LOCKS 76 /* user */
240 #define _SC_REGEXP 77 /* user */
241 #define _SC_SHELL 78 /* user */
242 #define _SC_SPAWN 79 /* user */
243 #define _SC_SPIN_LOCKS 80 /* user */
244 #define _SC_SPORADIC_SERVER 81
245 #define _SC_THREAD_ATTR_STACKADDR 82 /* user */
246 #define _SC_THREAD_ATTR_STACKSIZE 83 /* user */
247 #define _SC_THREAD_CPUTIME 84 /* user */
248 #define _SC_THREAD_DESTRUCTOR_ITERATIONS 85 /* user */
249 #define _SC_THREAD_KEYS_MAX 86 /* user */
250 #define _SC_THREAD_PRIO_INHERIT 87 /* user */
251 #define _SC_THREAD_PRIO_PROTECT 88 /* user */
252 #define _SC_THREAD_PRIORITY_SCHEDULING 89 /* user */
253 #define _SC_THREAD_PROCESS_SHARED 90 /* user */
254 #define _SC_THREAD_SAFE_FUNCTIONS 91 /* user */
255 #define _SC_THREAD_SPORADIC_SERVER 92 /* user */
256 #define _SC_THREAD_STACK_MIN 93 /* user */
257 #define _SC_THREAD_THREADS_MAX 94 /* user */
258 #define _SC_TIMEOUTS 95 /* user */
259 #define _SC_THREADS 96 /* user */
260 #define _SC_TRACE 97 /* user */
261 #define _SC_TRACE_EVENT_FILTER 98 /* user */
262 #define _SC_TRACE_INHERIT 99 /* user */
263 #define _SC_TRACE_LOG 100 /* user */
264 #define _SC_TTY_NAME_MAX 101 /* user */
265 #define _SC_TYPED_MEMORY_OBJECTS 102
266 #define _SC_V6_ILP32_OFF32 103 /* user */
267 #define _SC_V6_ILP32_OFFBIG 104 /* user */
268 #define _SC_V6_LP64_OFF64 105 /* user */
269 #define _SC_V6_LPBIG_OFFBIG 106 /* user */
271 #define _SC_RAW_SOCKETS 119
272 #define _SC_SYMLOOP_MAX 120
276 #define _SC_ATEXIT_MAX 107 /* user */
277 #define _SC_IOV_MAX 56
278 #define _SC_PAGE_SIZE _SC_PAGESIZE
279 #define _SC_XOPEN_CRYPT 108 /* user */
280 #define _SC_XOPEN_ENH_I18N 109 /* user */
281 #define _SC_XOPEN_LEGACY 110 /* user */
282 #define _SC_XOPEN_REALTIME 111
283 #define _SC_XOPEN_REALTIME_THREADS 112
284 #define _SC_XOPEN_SHM 113
285 #define _SC_XOPEN_STREAMS 114
286 #define _SC_XOPEN_UNIX 115
287 #define _SC_XOPEN_VERSION 116
288 #define _SC_XOPEN_XCU_VERSION 117 /* user */
292 #define _SC_NPROCESSORS_CONF 57
293 #define _SC_NPROCESSORS_ONLN 58
294 #define _SC_CPUSET_SIZE 122
297 /* Extensions found in Solaris and Linux. */
298 #define _SC_PHYS_PAGES 121
300 /* Keys for the confstr(3) function. */
301 #if __POSIX_VISIBLE >= 199209
302 #define _CS_PATH 1 /* default value of PATH */
305 #if __POSIX_VISIBLE >= 200112
306 #define _CS_POSIX_V6_ILP32_OFF32_CFLAGS 2
307 #define _CS_POSIX_V6_ILP32_OFF32_LDFLAGS 3
308 #define _CS_POSIX_V6_ILP32_OFF32_LIBS 4
309 #define _CS_POSIX_V6_ILP32_OFFBIG_CFLAGS 5
310 #define _CS_POSIX_V6_ILP32_OFFBIG_LDFLAGS 6
311 #define _CS_POSIX_V6_ILP32_OFFBIG_LIBS 7
312 #define _CS_POSIX_V6_LP64_OFF64_CFLAGS 8
313 #define _CS_POSIX_V6_LP64_OFF64_LDFLAGS 9
314 #define _CS_POSIX_V6_LP64_OFF64_LIBS 10
315 #define _CS_POSIX_V6_LPBIG_OFFBIG_CFLAGS 11
316 #define _CS_POSIX_V6_LPBIG_OFFBIG_LDFLAGS 12
317 #define _CS_POSIX_V6_LPBIG_OFFBIG_LIBS 13
318 #define _CS_POSIX_V6_WIDTH_RESTRICTED_ENVS 14
323 void _exit(int) __dead2;
324 int access(const char *, int);
325 unsigned int alarm(unsigned int);
326 int chdir(const char *);
327 int chown(const char *, uid_t, gid_t);
332 int execl(const char *, const char *, ...) __null_sentinel;
333 int execle(const char *, const char *, ...);
334 int execlp(const char *, const char *, ...) __null_sentinel;
335 int execv(const char *, char * const *);
336 int execve(const char *, char * const *, char * const *);
337 int execvp(const char *, char * const *);
339 long fpathconf(int, int);
340 char *getcwd(char *, size_t);
344 int getgroups(int, gid_t []);
345 char *getlogin(void);
351 int link(const char *, const char *);
352 #ifndef _LSEEK_DECLARED
353 #define _LSEEK_DECLARED
354 off_t lseek(int, off_t, int);
356 long pathconf(const char *, int);
359 ssize_t read(int, void *, size_t);
360 int rmdir(const char *);
362 int setpgid(pid_t, pid_t);
365 unsigned int sleep(unsigned int);
367 pid_t tcgetpgrp(int);
368 int tcsetpgrp(int, pid_t);
370 int ttyname_r(int, char *, size_t);
371 int unlink(const char *);
372 ssize_t write(int, const void *, size_t);
375 #if __POSIX_VISIBLE >= 199209 || __XSI_VISIBLE
376 size_t confstr(int, char *, size_t);
377 #ifndef _GETOPT_DECLARED
378 #define _GETOPT_DECLARED
379 int getopt(int, char * const [], const char *);
381 extern char *optarg; /* getopt(3) external variables */
382 extern int optind, opterr, optopt;
383 #endif /* _GETOPT_DECLARED */
386 /* ISO/IEC 9945-1: 1996 */
387 #if __POSIX_VISIBLE >= 199506 || __XSI_VISIBLE
392 * ftruncate() was in the POSIX Realtime Extension (it's used for shared
393 * memory), but truncate() was not.
395 #ifndef _FTRUNCATE_DECLARED
396 #define _FTRUNCATE_DECLARED
397 int ftruncate(int, off_t);
401 #if __POSIX_VISIBLE >= 199506
402 int getlogin_r(char *, int);
406 #if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE
407 int fchown(int, uid_t, gid_t);
408 ssize_t readlink(const char * __restrict, char * __restrict, size_t);
410 #if __POSIX_VISIBLE >= 200112
411 int gethostname(char *, size_t);
417 #if __POSIX_VISIBLE >= 200809 || __XSI_VISIBLE
418 int getsid(pid_t _pid);
420 int getpgid(pid_t _pid);
421 int lchown(const char *, uid_t, gid_t);
422 ssize_t pread(int, void *, size_t, off_t);
423 ssize_t pwrite(int, const void *, size_t, off_t);
425 /* See comment at ftruncate() above. */
426 #ifndef _TRUNCATE_DECLARED
427 #define _TRUNCATE_DECLARED
428 int truncate(const char *, off_t);
430 #endif /* __POSIX_VISIBLE >= 200809 || __XSI_VISIBLE */
432 #if __POSIX_VISIBLE >= 200809
433 int faccessat(int, const char *, int, int);
434 int fchownat(int, const char *, uid_t, gid_t, int);
435 int fexecve(int, char *const [], char *const []);
436 int linkat(int, const char *, int, const char *, int);
437 ssize_t readlinkat(int, const char * __restrict, char * __restrict, size_t);
438 int symlinkat(const char *, int, const char *);
439 int unlinkat(int, const char *, int);
440 #endif /* __POSIX_VISIBLE >= 200809 */
443 * symlink() was originally in POSIX.1a, which was withdrawn after
444 * being overtaken by events (1003.1-2001). It was in XPG4.2, and of
445 * course has been in BSD since 4.2.
447 #if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE >= 402
448 int symlink(const char * __restrict, const char * __restrict);
451 /* X/Open System Interfaces */
453 char *crypt(const char *, const char *);
454 long gethostid(void);
455 int lockf(int, int, off_t);
457 int setregid(gid_t, gid_t);
458 int setreuid(uid_t, uid_t);
460 #ifndef _SWAB_DECLARED
461 #define _SWAB_DECLARED
462 void swab(const void * __restrict, void * __restrict, ssize_t);
463 #endif /* _SWAB_DECLARED */
467 #endif /* __XSI_VISIBLE */
469 #if (__XSI_VISIBLE && __XSI_VISIBLE <= 500) || __BSD_VISIBLE
470 int brk(const void *);
471 int chroot(const char *);
472 int getdtablesize(void);
473 int getpagesize(void) __pure2;
474 char *getpass(const char *);
475 void *sbrk(intptr_t);
478 #if (__XSI_VISIBLE && __XSI_VISIBLE <= 600) || __BSD_VISIBLE
479 char *getwd(char *); /* obsoleted by getcwd() */
481 ualarm(useconds_t, useconds_t);
482 int usleep(useconds_t);
483 pid_t vfork(void) __returns_twice;
487 struct timeval; /* select(2) */
490 int initialized; /* For compatibility with glibc. */
491 char __buf[256]; /* Buffer returned by crypt_r(). */
494 int acct(const char *);
495 int async_daemon(void);
496 int check_utility_compat(const char *);
498 crypt_get_format(void);
499 char *crypt_r(const char *, const char *, struct crypt_data *);
500 int crypt_set_format(const char *);
501 int dup3(int, int, int);
502 int eaccess(const char *, int);
503 void endusershell(void);
504 int exect(const char *, char * const *, char * const *);
505 int execvP(const char *, const char *, char * const *);
506 int feature_present(const char *);
507 char *fflagstostr(u_long);
508 int getdomainname(char *, int);
509 int getentropy(void *, size_t);
510 int getgrouplist(const char *, gid_t, gid_t *, int *);
511 int getloginclass(char *, size_t);
512 mode_t getmode(const void *, mode_t);
513 int getosreldate(void);
514 int getpeereid(int, uid_t *, gid_t *);
515 int getresgid(gid_t *, gid_t *, gid_t *);
516 int getresuid(uid_t *, uid_t *, uid_t *);
517 char *getusershell(void);
518 int initgroups(const char *, gid_t);
519 int iruserok(unsigned long, int, const char *, const char *);
520 int iruserok_sa(const void *, int, int, const char *, const char *);
522 void __FreeBSD_libc_enter_restricted_mode(void);
523 long lpathconf(const char *, int);
524 #ifndef _MKDTEMP_DECLARED
525 char *mkdtemp(char *);
526 #define _MKDTEMP_DECLARED
528 #ifndef _MKNOD_DECLARED
529 int mknod(const char *, mode_t, dev_t);
530 #define _MKNOD_DECLARED
532 #ifndef _MKSTEMP_DECLARED
534 #define _MKSTEMP_DECLARED
536 int mkstemps(char *, int);
537 #ifndef _MKTEMP_DECLARED
538 char *mktemp(char *);
539 #define _MKTEMP_DECLARED
541 int nfssvc(int, void *);
542 int nlm_syscall(int, int, int, char **);
543 int pipe2(int *, int);
544 int profil(char *, size_t, vm_offset_t, int);
545 int rcmd(char **, int, const char *, const char *, const char *, int *);
546 int rcmd_af(char **, int, const char *,
547 const char *, const char *, int *, int);
548 int rcmdsh(char **, int, const char *,
549 const char *, const char *, const char *);
550 char *re_comp(const char *);
551 int re_exec(const char *);
553 int revoke(const char *);
555 pid_t rfork_thread(int, void *, int (*)(void *), void *);
556 int rresvport(int *);
557 int rresvport_af(int *, int);
558 int ruserok(const char *, int, const char *, const char *);
560 #ifndef _SELECT_DECLARED
561 #define _SELECT_DECLARED
562 int select(int, fd_set *, fd_set *, fd_set *, struct timeval *);
565 int setdomainname(const char *, int);
566 int setgroups(int, const gid_t *);
567 void sethostid(long);
568 int sethostname(const char *, int);
569 int setlogin(const char *);
570 int setloginclass(const char *);
571 void *setmode(const char *);
572 int setpgrp(pid_t, pid_t); /* obsoleted by setpgid() */
573 void setproctitle(const char *_fmt, ...) __printf0like(1, 2);
574 void setproctitle_fast(const char *_fmt, ...) __printf0like(1, 2);
575 int setresgid(gid_t, gid_t, gid_t);
576 int setresuid(uid_t, uid_t, uid_t);
579 void setusershell(void);
580 int strtofflags(char **, u_long *, u_long *);
581 int swapon(const char *);
582 int swapoff(const char *);
583 int syscall(int, ...);
584 off_t __syscall(quad_t, ...);
585 int undelete(const char *);
586 int unwhiteout(const char *);
587 void *valloc(size_t); /* obsoleted by malloc() */
589 #ifndef _OPTRESET_DECLARED
590 #define _OPTRESET_DECLARED
591 extern int optreset; /* getopt(3) external variable */
593 #endif /* __BSD_VISIBLE */
596 #endif /* !_UNISTD_H_ */