xref: /freebsd/lib/libc/gen/sysconf.c (revision a3e8fd0b7f663db7eafff527d5c3ca3bcfa8a537)
1 /*-
2  * Copyright (c) 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Sean Eric Fagan of Cygnus Support.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char sccsid[] = "@(#)sysconf.c	8.2 (Berkeley) 3/20/94";
39 #endif /* LIBC_SCCS and not lint */
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include <sys/param.h>
44 #include <sys/time.h>
45 #include <sys/sysctl.h>
46 #include <sys/resource.h>
47 
48 #include <errno.h>
49 #include <limits.h>
50 #include <paths.h>
51 #include <pthread.h>		/* we just need the limits */
52 #include <time.h>
53 #include <unistd.h>
54 
55 #include "../stdlib/atexit.h"
56 #include "../stdtime/tzfile.h"
57 
58 #define	_PATH_ZONEINFO	TZDIR	/* from tzfile.h */
59 
60 /*
61  * sysconf --
62  *	get configurable system variables.
63  *
64  * XXX
65  * POSIX 1003.1 (ISO/IEC 9945-1, 4.8.1.3) states that the variable values
66  * not change during the lifetime of the calling process.  This would seem
67  * to require that any change to system limits kill all running processes.
68  * A workaround might be to cache the values when they are first retrieved
69  * and then simply return the cached value on subsequent calls.  This is
70  * less useful than returning up-to-date values, however.
71  */
72 long
73 sysconf(name)
74 	int name;
75 {
76 	struct rlimit rl;
77 	size_t len;
78 	int mib[2], sverrno, value;
79 	long defaultresult;
80 	const char *path;
81 
82 	len = sizeof(value);
83 	defaultresult = -1;
84 
85 	switch (name) {
86 	case _SC_ARG_MAX:
87 		mib[0] = CTL_KERN;
88 		mib[1] = KERN_ARGMAX;
89 		break;
90 	case _SC_CHILD_MAX:
91 		if (getrlimit(RLIMIT_NPROC, &rl) != 0)
92 			return (-1);
93 		if (rl.rlim_cur == RLIM_INFINITY)
94 			return (-1);
95 		if (rl.rlim_cur > LONG_MAX) {
96 			errno = EOVERFLOW;
97 			return (-1);
98 		}
99 		return ((long)rl.rlim_cur);
100 	case _SC_CLK_TCK:
101 		return (CLK_TCK);
102 	case _SC_NGROUPS_MAX:
103 		mib[0] = CTL_KERN;
104 		mib[1] = KERN_NGROUPS;
105 		break;
106 	case _SC_OPEN_MAX:
107 	case _SC_STREAM_MAX:	/* assume fds run out before memory does */
108 		if (getrlimit(RLIMIT_NOFILE, &rl) != 0)
109 			return (-1);
110 		if (rl.rlim_cur == RLIM_INFINITY)
111 			return (-1);
112 		if (rl.rlim_cur > LONG_MAX) {
113 			errno = EOVERFLOW;
114 			return (-1);
115 		}
116 		return ((long)rl.rlim_cur);
117 	case _SC_JOB_CONTROL:
118 		return (_POSIX_JOB_CONTROL);
119 	case _SC_SAVED_IDS:
120 		/* XXX - must be 1 */
121 		mib[0] = CTL_KERN;
122 		mib[1] = KERN_SAVED_IDS;
123 		goto yesno;
124 	case _SC_VERSION:
125 		mib[0] = CTL_KERN;
126 		mib[1] = KERN_POSIX1;
127 		break;
128 	case _SC_BC_BASE_MAX:
129 		return (BC_BASE_MAX);
130 	case _SC_BC_DIM_MAX:
131 		return (BC_DIM_MAX);
132 	case _SC_BC_SCALE_MAX:
133 		return (BC_SCALE_MAX);
134 	case _SC_BC_STRING_MAX:
135 		return (BC_STRING_MAX);
136 	case _SC_COLL_WEIGHTS_MAX:
137 		return (COLL_WEIGHTS_MAX);
138 	case _SC_EXPR_NEST_MAX:
139 		return (EXPR_NEST_MAX);
140 	case _SC_LINE_MAX:
141 		return (LINE_MAX);
142 	case _SC_RE_DUP_MAX:
143 		return (RE_DUP_MAX);
144 	case _SC_2_VERSION:
145 		/*
146 		 * This is something of a lie, but it would be silly at
147 		 * this point to try to deduce this from the contents
148 		 * of the filesystem.
149 		 */
150 		return (_POSIX2_VERSION);
151 	case _SC_2_C_BIND:
152 		return (_POSIX2_C_BIND);
153 	case _SC_2_C_DEV:
154 		return (_POSIX2_C_DEV);
155 	case _SC_2_CHAR_TERM:
156 		return (_POSIX2_CHAR_TERM);
157 	case _SC_2_FORT_DEV:
158 		return (_POSIX2_FORT_DEV);
159 	case _SC_2_FORT_RUN:
160 		return (_POSIX2_FORT_RUN);
161 	case _SC_2_LOCALEDEF:
162 		return (_POSIX2_LOCALEDEF);
163 	case _SC_2_SW_DEV:
164 		return (_POSIX2_SW_DEV);
165 	case _SC_2_UPE:
166 		return (_POSIX2_UPE);
167 	case _SC_TZNAME_MAX:
168 		path = _PATH_ZONEINFO;
169 do_NAME_MAX:
170 		sverrno = errno;
171 		errno = 0;
172 		value = pathconf(path, _PC_NAME_MAX);
173 		if (value == -1 && errno != 0)
174 			return (-1);
175 		errno = sverrno;
176 		return (value);
177 
178 	case _SC_ASYNCHRONOUS_IO:
179 		mib[0] = CTL_P1003_1B;
180 		mib[1] = CTL_P1003_1B_ASYNCHRONOUS_IO;
181 		goto yesno;
182 	case _SC_MAPPED_FILES:
183 		return (_POSIX_MAPPED_FILES);
184 	case _SC_MEMLOCK:
185 		return (_POSIX_MEMLOCK);
186 	case _SC_MEMLOCK_RANGE:
187 		return (_POSIX_MEMLOCK_RANGE);
188 	case _SC_MEMORY_PROTECTION:
189 		return (_POSIX_MEMORY_PROTECTION);
190 	case _SC_MESSAGE_PASSING:
191 #if _POSIX_MESSAGE_PASSING == 0
192 		mib[0] = CTL_P1003_1B;
193 		mib[1] = CTL_P1003_1B_MESSAGE_PASSING;
194 		goto yesno;
195 #else
196 		return (_POSIX_MESSAGE_PASSING);
197 #endif
198 	case _SC_PRIORITIZED_IO:
199 #if _POSIX_PRIORITIZED_IO == 0
200 		mib[0] = CTL_P1003_1B;
201 		mib[1] = CTL_P1003_1B_PRIORITIZED_IO;
202 		goto yesno;
203 #else
204 		return (_POSIX_PRIORITIZED_IO);
205 #endif
206 	case _SC_PRIORITY_SCHEDULING:
207 #if _POSIX_PRIORITY_SCHEDULING == 0
208 		mib[0] = CTL_P1003_1B;
209 		mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING;
210 		goto yesno;
211 #else
212 		return (_POSIX_PRIORITY_SCHEDULING);
213 #endif
214 	case _SC_REALTIME_SIGNALS:
215 #if _POSIX_REALTIME_SIGNALS == 0
216 		mib[0] = CTL_P1003_1B;
217 		mib[1] = CTL_P1003_1B_REALTIME_SIGNALS;
218 		goto yesno;
219 #else
220 		return (_POSIX_REALTIME_SIGNALS);
221 #endif
222 	case _SC_SEMAPHORES:
223 #if _POSIX_SEMAPHORES == 0
224 		mib[0] = CTL_P1003_1B;
225 		mib[1] = CTL_P1003_1B_SEMAPHORES;
226 		goto yesno;
227 #else
228 		return (_POSIX_SEMAPHORES);
229 #endif
230 	case _SC_FSYNC:
231 		return (_POSIX_FSYNC);
232 
233 	case _SC_SHARED_MEMORY_OBJECTS:
234 		return (_POSIX_SHARED_MEMORY_OBJECTS);
235 	case _SC_SYNCHRONIZED_IO:
236 #if _POSIX_SYNCHRONIZED_IO == 0
237 		mib[0] = CTL_P1003_1B;
238 		mib[1] = CTL_P1003_1B_SYNCHRONIZED_IO;
239 		goto yesno;
240 #else
241 		return (_POSIX_SYNCHRONIZED_IO);
242 #endif
243 	case _SC_TIMERS:
244 #if _POSIX_TIMERS == 0
245 		mib[0] = CTL_P1003_1B;
246 		mib[1] = CTL_P1003_1B_TIMERS;
247 		goto yesno;
248 #else
249 		return (_POSIX_TIMERS);
250 #endif
251 	case _SC_AIO_LISTIO_MAX:
252 		mib[0] = CTL_P1003_1B;
253 		mib[1] = CTL_P1003_1B_AIO_LISTIO_MAX;
254 		goto yesno;
255 	case _SC_AIO_MAX:
256 		mib[0] = CTL_P1003_1B;
257 		mib[1] = CTL_P1003_1B_AIO_MAX;
258 		goto yesno;
259 	case _SC_AIO_PRIO_DELTA_MAX:
260 		mib[0] = CTL_P1003_1B;
261 		mib[1] = CTL_P1003_1B_AIO_PRIO_DELTA_MAX;
262 		goto yesno;
263 	case _SC_DELAYTIMER_MAX:
264 		mib[0] = CTL_P1003_1B;
265 		mib[1] = CTL_P1003_1B_DELAYTIMER_MAX;
266 		goto yesno;
267 	case _SC_MQ_OPEN_MAX:
268 		mib[0] = CTL_P1003_1B;
269 		mib[1] = CTL_P1003_1B_MQ_OPEN_MAX;
270 		goto yesno;
271 	case _SC_PAGESIZE:
272 		defaultresult = getpagesize();
273 		mib[0] = CTL_P1003_1B;
274 		mib[1] = CTL_P1003_1B_PAGESIZE;
275 		goto yesno;
276 	case _SC_RTSIG_MAX:
277 		mib[0] = CTL_P1003_1B;
278 		mib[1] = CTL_P1003_1B_RTSIG_MAX;
279 		goto yesno;
280 	case _SC_SEM_NSEMS_MAX:
281 		mib[0] = CTL_P1003_1B;
282 		mib[1] = CTL_P1003_1B_SEM_NSEMS_MAX;
283 		goto yesno;
284 	case _SC_SEM_VALUE_MAX:
285 		mib[0] = CTL_P1003_1B;
286 		mib[1] = CTL_P1003_1B_SEM_VALUE_MAX;
287 		goto yesno;
288 	case _SC_SIGQUEUE_MAX:
289 		mib[0] = CTL_P1003_1B;
290 		mib[1] = CTL_P1003_1B_SIGQUEUE_MAX;
291 		goto yesno;
292 	case _SC_TIMER_MAX:
293 		mib[0] = CTL_P1003_1B;
294 		mib[1] = CTL_P1003_1B_TIMER_MAX;
295 
296 yesno:		if (sysctl(mib, 2, &value, &len, NULL, 0) == -1)
297 			return (-1);
298 		if (value == 0)
299 			return (defaultresult);
300 		return (value);
301 
302 	case _SC_2_PBS:
303 	case _SC_2_PBS_ACCOUNTING:
304 	case _SC_2_PBS_CHECKPOINT:
305 	case _SC_2_PBS_LOCATE:
306 	case _SC_2_PBS_MESSAGE:
307 	case _SC_2_PBS_TRACK:
308 #if _POSIX2_PBS == 0
309 #error "don't know how to determine _SC_2_PBS"
310 		/*
311 		 * This probably requires digging through the filesystem
312 		 * to see if the appropriate package has been installed.
313 		 * Since we don't currently support this option at all,
314 		 * it's not worth the effort to write the code now.
315 		 * Figuring out which of the sub-options are supported
316 		 * would be even more difficult, so it's probably easier
317 		 * to always say ``no''.
318 		 */
319 #else
320 		return (_POSIX2_PBS);
321 #endif
322 	case _SC_ADVISORY_INFO:
323 #if _POSIX_ADVISORY_INFO == 0
324 #error "_POSIX_ADVISORY_INFO"
325 #else
326 		return (_POSIX_ADVISORY_INFO);
327 #endif
328 	case _SC_BARRIERS:
329 #if _POSIX_BARRIERS == 0
330 #error "_POSIX_BARRIERS"
331 #else
332 		return (_POSIX_BARRIERS);
333 #endif
334 	case _SC_CLOCK_SELECTION:
335 #if _POSIX_CLOCK_SELECTION == 0
336 #error "_POSIX_CLOCK_SELECTION"
337 #else
338 		return (_POSIX_CLOCK_SELECTION);
339 #endif
340 	case _SC_CPUTIME:
341 #if _POSIX_CPUTIME == 0
342 #error "_POSIX_CPUTIME"
343 #else
344 		return (_POSIX_CPUTIME);
345 #endif
346 #ifdef notdef
347 	case _SC_FILE_LOCKING:
348 		/*
349 		 * XXX - The standard doesn't tell us how to define
350 		 * _POSIX_FILE_LOCKING, so we can't answer this one.
351 		 */
352 #endif
353 #if _POSIX_THREAD_SAFE_FUNCTIONS > -1
354 	case _SC_GETGR_R_SIZE_MAX:
355 	case _SC_GETPW_R_SIZE_MAX:
356 #error "somebody needs to implement this"
357 #endif
358 	case _SC_HOST_NAME_MAX:
359 		return (MAXHOSTNAMELEN - 1); /* does not include \0 */
360 	case _SC_LOGIN_NAME_MAX:
361 		return (MAXLOGNAME);
362 	case _SC_MONOTONIC_CLOCK:
363 #if _POSIX_MONOTONIC_CLOCK == 0
364 #error "_POSIX_MONOTONIC_CLOCK"
365 #else
366 		return (_POSIX_MONOTONIC_CLOCK);
367 #endif
368 #if _POSIX_MESSAGE_PASSING > -1
369 	case _SC_MQ_PRIO_MAX:
370 		return (MQ_PRIO_MAX);
371 #endif
372 	case _SC_READER_WRITER_LOCKS:
373 		return (_POSIX_READER_WRITER_LOCKS);
374 	case _SC_REGEXP:
375 		return (_POSIX_REGEXP);
376 	case _SC_SHELL:
377 		return (_POSIX_SHELL);
378 	case _SC_SPAWN:
379 		return (_POSIX_SPAWN);
380 	case _SC_SPIN_LOCKS:
381 		return (_POSIX_SPIN_LOCKS);
382 	case _SC_SPORADIC_SERVER:
383 #if _POSIX_SPORADIC_SERVER == 0
384 #error "_POSIX_SPORADIC_SERVER"
385 #else
386 		return (_POSIX_SPORADIC_SERVER);
387 #endif
388 	case _SC_THREAD_ATTR_STACKADDR:
389 		return (_POSIX_THREAD_ATTR_STACKADDR);
390 	case _SC_THREAD_ATTR_STACKSIZE:
391 		return (_POSIX_THREAD_ATTR_STACKSIZE);
392 	case _SC_THREAD_CPUTIME:
393 		return (_POSIX_THREAD_CPUTIME);
394 	case _SC_THREAD_DESTRUCTOR_ITERATIONS:
395 		return (PTHREAD_DESTRUCTOR_ITERATIONS);
396 	case _SC_THREAD_KEYS_MAX:
397 		return (PTHREAD_KEYS_MAX);
398 	case _SC_THREAD_PRIO_INHERIT:
399 		return (_POSIX_THREAD_PRIO_INHERIT);
400 	case _SC_THREAD_PRIO_PROTECT:
401 		return (_POSIX_THREAD_PRIO_PROTECT);
402 	case _SC_THREAD_PRIORITY_SCHEDULING:
403 		return (_POSIX_THREAD_PRIORITY_SCHEDULING);
404 	case _SC_THREAD_PROCESS_SHARED:
405 		return (_POSIX_THREAD_PROCESS_SHARED);
406 	case _SC_THREAD_SAFE_FUNCTIONS:
407 		return (_POSIX_THREAD_SAFE_FUNCTIONS);
408 	case _SC_THREAD_STACK_MIN:
409 		return (PTHREAD_STACK_MIN);
410 	case _SC_THREAD_THREADS_MAX:
411 		return (PTHREAD_THREADS_MAX); /* XXX wrong type! */
412 	case _SC_TIMEOUTS:
413 		return (_POSIX_TIMEOUTS);
414 	case _SC_THREADS:
415 		return (_POSIX_THREADS);
416 	case _SC_TRACE:
417 #if _POSIX_TRACE == 0
418 #error "_POSIX_TRACE"
419 		/* While you're implementing this, also do the ones below. */
420 #else
421 		return (_POSIX_TRACE);
422 #endif
423 #if _POSIX_TRACE > -1
424 	case _SC_TRACE_EVENT_FILTER:
425 		return (_POSIX_TRACE_EVENT_FILTER);
426 	case _SC_TRACE_INHERIT:
427 		return (_POSIX_TRACE_INHERIT);
428 	case _SC_TRACE_LOG:
429 		return (_POSIX_TRACE_LOG);
430 #endif
431 	case _SC_TTY_NAME_MAX:
432 		path = _PATH_DEV;
433 		goto do_NAME_MAX;
434 	case _SC_TYPED_MEMORY_OBJECTS:
435 #if _POSIX_TYPED_MEMORY_OBJECTS == 0
436 #error "_POSIX_TYPED_MEMORY_OBJECTS"
437 #else
438 		return (_POSIX_TYPED_MEMORY_OBJECTS);
439 #endif
440 	case _SC_V6_ILP32_OFF32:
441 #if _V6_ILP32_OFF32 == 0
442 		if (sizeof(int) * CHAR_BIT == 32 &&
443 		    sizeof(int) == sizeof(long) &&
444 		    sizeof(long) == sizeof(void *) &&
445 		    sizeof(void *) == sizeof(off_t))
446 			return 1;
447 		else
448 			return -1;
449 #else
450 		return (_V6_ILP32_OFF32);
451 #endif
452 	case _SC_V6_ILP32_OFFBIG:
453 #if _V6_ILP32_OFFBIG == 0
454 		if (sizeof(int) * CHAR_BIT == 32 &&
455 		    sizeof(int) == sizeof(long) &&
456 		    sizeof(long) == sizeof(void *) &&
457 		    sizeof(off_t) * CHAR_BIT >= 64)
458 			return 1;
459 		else
460 			return -1;
461 #else
462 		return (_V6_ILP32_OFFBIG);
463 #endif
464 	case _SC_V6_LP64_OFF64:
465 #if _V6_LP64_OFF64 == 0
466 		if (sizeof(int) * CHAR_BIT == 32 &&
467 		    sizeof(long) * CHAR_BIT == 64 &&
468 		    sizeof(long) == sizeof(void *) &&
469 		    sizeof(void *) == sizeof(off_t))
470 			return 1;
471 		else
472 			return -1;
473 #else
474 		return (_V6_LP64_OFF64);
475 #endif
476 	case _SC_V6_LPBIG_OFFBIG:
477 #if _V6_LPBIG_OFFBIG == 0
478 		if (sizeof(int) * CHAR_BIT >= 32 &&
479 		    sizeof(long) * CHAR_BIT >= 64 &&
480 		    sizeof(void *) * CHAR_BIT >= 64 &&
481 		    sizeof(off_t) * CHAR_BIT >= 64)
482 			return 1;
483 		else
484 			return -1;
485 #else
486 		return (_V6_LPBIG_OFFBIG);
487 #endif
488 	case _SC_ATEXIT_MAX:
489 		return (ATEXIT_SIZE);
490 	case _SC_IOV_MAX:
491 		mib[0] = CTL_KERN;
492 		mib[1] = KERN_IOV_MAX;
493 		break;
494 	case _SC_XOPEN_CRYPT:
495 		return (_XOPEN_CRYPT);
496 	case _SC_XOPEN_ENH_I18N:
497 		return (_XOPEN_ENH_I18N);
498 	case _SC_XOPEN_LEGACY:
499 		return (_XOPEN_LEGACY);
500 	case _SC_XOPEN_REALTIME:
501 #if _XOPEN_REALTIME == 0
502 		sverrno = errno;
503 		value = sysconf(_SC_ASYNCHRONOUS_IO) > 0 &&
504 			sysconf(_SC_MEMLOCK) > 0 &&
505 			sysconf(_SC_MEMLOCK_RANGE) > 0 &&
506 			sysconf(_SC_MESSAGE_PASSING) > 0 &&
507 			sysconf(_SC_PRIORITY_SCHEDULING) > 0 &&
508 			sysconf(_SC_REALTIME_SIGNALS) > 0 &&
509 			sysconf(_SC_SEMAPHORES) > 0 &&
510 			sysconf(_SC_SHARED_MEMORY_OBJECTS) > 0 &&
511 			sysconf(_SC_SYNCHRONIZED_IO) > 0 &&
512 			sysconf(_SC_TIMERS) > 0;
513 		errno = sverrno;
514 		if (value)
515 			return (200112L);
516 		else
517 			return (-1);
518 #else
519 		return (_XOPEN_REALTIME);
520 #endif
521 	case _SC_XOPEN_REALTIME_THREADS:
522 #if _XOPEN_REALTIME_THREADS == 0
523 #error "_XOPEN_REALTIME_THREADS"
524 #else
525 		return (_XOPEN_REALTIME_THREADS);
526 #endif
527 	case _SC_XOPEN_SHM:
528 		sverrno = errno;
529 		if (sysctlbyname("kern.ipc.shmmin", &value, &len, NULL,
530 		    0) == -1) {
531 			errno = sverrno;
532 			return (-1);
533 		}
534 		errno = sverrno;
535 		return (1);
536 	case _SC_XOPEN_STREAMS:
537 		return (_XOPEN_STREAMS);
538 	case _SC_XOPEN_UNIX:
539 		return (_XOPEN_UNIX);
540 #ifdef _XOPEN_VERSION
541 	case _SC_XOPEN_VERSION:
542 		return (_XOPEN_VERSION);
543 #endif
544 #ifdef _XOPEN_XCU_VERSION
545 	case _SC_XOPEN_XCU_VERSION:
546 		return (_XOPEN_XCU_VERSION);
547 #endif
548 
549 	case _SC_NPROCESSORS_CONF:
550 	case _SC_NPROCESSORS_ONLN:
551 		mib[0] = CTL_HW;
552 		mib[1] = HW_NCPU;
553 		break;
554 
555 	default:
556 		errno = EINVAL;
557 		return (-1);
558 	}
559 	return (sysctl(mib, 2, &value, &len, NULL, 0) == -1 ? -1 : value);
560 }
561