xref: /freebsd/usr.bin/ipcs/ipcs.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
1 /*
2  * Copyright (c) 1994 SigmaSoft, Th. Lockert <tholo@sigmasoft.com>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
17  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
18  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
19  * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #ifndef lint
29 static const char rcsid[] =
30   "$FreeBSD$";
31 #endif /* not lint */
32 
33 #include <assert.h>
34 #include <err.h>
35 #include <fcntl.h>
36 #include <kvm.h>
37 #include <nlist.h>
38 #include <limits.h>
39 #include <paths.h>
40 #include <stddef.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 
46 #include <sys/types.h>
47 #include <sys/param.h>
48 #include <sys/time.h>
49 #include <sys/proc.h>
50 #include <sys/sysctl.h>
51 #define _KERNEL
52 #include <sys/ipc.h>
53 #include <sys/sem.h>
54 #include <sys/shm.h>
55 #include <sys/msg.h>
56 
57 /* SysCtlGatherStruct structure. */
58 struct scgs_vector {
59 	const char *sysctl;
60 	off_t offset;
61 	size_t size;
62 };
63 
64 int	use_sysctl = 1;
65 struct semid_ds	*sema;
66 struct seminfo	seminfo;
67 struct msginfo	msginfo;
68 struct msqid_ds	*msqids;
69 struct shminfo	shminfo;
70 struct shmid_ds	*shmsegs;
71 
72 void	sysctlgatherstruct __P((void *addr, size_t size,
73     struct scgs_vector *vec));
74 void	kget __P((int idx, void *addr, size_t size));
75 void	usage __P((void));
76 
77 static struct nlist symbols[] = {
78 	{"sema"},
79 #define X_SEMA		0
80 	{"seminfo"},
81 #define X_SEMINFO	1
82 	{"msginfo"},
83 #define X_MSGINFO	2
84 	{"msqids"},
85 #define X_MSQIDS	3
86 	{"shminfo"},
87 #define X_SHMINFO	4
88 	{"shmsegs"},
89 #define X_SHMSEGS	5
90 	{NULL}
91 };
92 
93 #define	SHMINFO_XVEC				\
94 X(shmmax, sizeof(int))				\
95 X(shmmin, sizeof(int))				\
96 X(shmmni, sizeof(int))				\
97 X(shmseg, sizeof(int))				\
98 X(shmall, sizeof(int))
99 
100 #define	SEMINFO_XVEC				\
101 X(semmap, sizeof(int))				\
102 X(semmni, sizeof(int))				\
103 X(semmns, sizeof(int))				\
104 X(semmnu, sizeof(int))				\
105 X(semmsl, sizeof(int))				\
106 X(semopm, sizeof(int))				\
107 X(semume, sizeof(int))				\
108 X(semusz, sizeof(int))				\
109 X(semvmx, sizeof(int))				\
110 X(semaem, sizeof(int))
111 
112 #define	MSGINFO_XVEC				\
113 X(msgmax, sizeof(int))				\
114 X(msgmni, sizeof(int))				\
115 X(msgmnb, sizeof(int))				\
116 X(msgtql, sizeof(int))				\
117 X(msgssz, sizeof(int))				\
118 X(msgseg, sizeof(int))
119 
120 #define	X(a, b)	{ "kern.ipc." #a, offsetof(TYPEC, a), (b) },
121 #define	TYPEC	struct shminfo
122 struct scgs_vector shminfo_scgsv[] = { SHMINFO_XVEC { NULL } };
123 #undef	TYPEC
124 #define	TYPEC	struct seminfo
125 struct scgs_vector seminfo_scgsv[] = { SEMINFO_XVEC { NULL } };
126 #undef	TYPEC
127 #define	TYPEC	struct msginfo
128 struct scgs_vector msginfo_scgsv[] = { MSGINFO_XVEC { NULL } };
129 #undef	TYPEC
130 #undef	X
131 
132 static kvm_t *kd;
133 
134 char   *
135 fmt_perm(mode)
136 	u_short mode;
137 {
138 	static char buffer[100];
139 
140 	buffer[0] = '-';
141 	buffer[1] = '-';
142 	buffer[2] = ((mode & 0400) ? 'r' : '-');
143 	buffer[3] = ((mode & 0200) ? 'w' : '-');
144 	buffer[4] = ((mode & 0100) ? 'a' : '-');
145 	buffer[5] = ((mode & 0040) ? 'r' : '-');
146 	buffer[6] = ((mode & 0020) ? 'w' : '-');
147 	buffer[7] = ((mode & 0010) ? 'a' : '-');
148 	buffer[8] = ((mode & 0004) ? 'r' : '-');
149 	buffer[9] = ((mode & 0002) ? 'w' : '-');
150 	buffer[10] = ((mode & 0001) ? 'a' : '-');
151 	buffer[11] = '\0';
152 	return (&buffer[0]);
153 }
154 
155 void
156 cvt_time(t, buf)
157 	time_t  t;
158 	char   *buf;
159 {
160 	struct tm *tm;
161 
162 	if (t == 0) {
163 		strcpy(buf, "no-entry");
164 	} else {
165 		tm = localtime(&t);
166 		sprintf(buf, "%2d:%02d:%02d",
167 			tm->tm_hour, tm->tm_min, tm->tm_sec);
168 	}
169 }
170 #define	SHMINFO		1
171 #define	SHMTOTAL	2
172 #define	MSGINFO		4
173 #define	MSGTOTAL	8
174 #define	SEMINFO		16
175 #define	SEMTOTAL	32
176 
177 #define BIGGEST		1
178 #define CREATOR		2
179 #define OUTSTANDING	4
180 #define PID		8
181 #define TIME		16
182 
183 int
184 main(argc, argv)
185 	int     argc;
186 	char   *argv[];
187 {
188 	int     display = SHMINFO | MSGINFO | SEMINFO;
189 	int     option = 0;
190 	char   *core = NULL, *namelist = NULL;
191 	char	kvmoferr[_POSIX2_LINE_MAX];  /* Error buf for kvm_openfiles. */
192 	int     i;
193 
194 	while ((i = getopt(argc, argv, "MmQqSsabC:cN:optTy")) != -1)
195 		switch (i) {
196 		case 'M':
197 			display = SHMTOTAL;
198 			break;
199 		case 'm':
200 			display = SHMINFO;
201 			break;
202 		case 'Q':
203 			display = MSGTOTAL;
204 			break;
205 		case 'q':
206 			display = MSGINFO;
207 			break;
208 		case 'S':
209 			display = SEMTOTAL;
210 			break;
211 		case 's':
212 			display = SEMINFO;
213 			break;
214 		case 'T':
215 			display = SHMTOTAL | MSGTOTAL | SEMTOTAL;
216 			break;
217 		case 'a':
218 			option |= BIGGEST | CREATOR | OUTSTANDING | PID | TIME;
219 			break;
220 		case 'b':
221 			option |= BIGGEST;
222 			break;
223 		case 'C':
224 			core = optarg;
225 			break;
226 		case 'c':
227 			option |= CREATOR;
228 			break;
229 		case 'N':
230 			namelist = optarg;
231 			break;
232 		case 'o':
233 			option |= OUTSTANDING;
234 			break;
235 		case 'p':
236 			option |= PID;
237 			break;
238 		case 't':
239 			option |= TIME;
240 			break;
241 		case 'y':
242 			use_sysctl = 0;
243 			break;
244 		default:
245 			usage();
246 		}
247 
248 	/*
249 	 * If paths to the exec file or core file were specified, we
250 	 * aren't operating on the running kernel, so we can't use
251 	 * sysctl.
252 	 */
253 	if (namelist != NULL || core != NULL)
254 		use_sysctl = 0;
255 
256 	if (!use_sysctl) {
257 		kd = kvm_openfiles(namelist, core, NULL, O_RDONLY, kvmoferr);
258 		if (kd == NULL)
259 			errx(1, "kvm_openfiles: %s", kvmoferr);
260 		switch (kvm_nlist(kd, symbols)) {
261 		case 0:
262 			break;
263 		case -1:
264 			errx(1, "unable to read kernel symbol table");
265 		default:
266 #ifdef notdef		/* they'll be told more civilly later */
267 			warnx("nlist failed");
268 			for (i = 0; symbols[i].n_name != NULL; i++)
269 				if (symbols[i].n_value == 0)
270 					warnx("symbol %s not found",
271 					    symbols[i].n_name);
272 			break;
273 #endif
274 		}
275 	}
276 
277 	kget(X_MSGINFO, &msginfo, sizeof(msginfo));
278 	if ((display & (MSGINFO | MSGTOTAL))) {
279 		if (display & MSGTOTAL) {
280 			printf("msginfo:\n");
281 			printf("\tmsgmax: %6d\t(max characters in a message)\n",
282 			    msginfo.msgmax);
283 			printf("\tmsgmni: %6d\t(# of message queues)\n",
284 			    msginfo.msgmni);
285 			printf("\tmsgmnb: %6d\t(max characters in a message queue)\n",
286 			    msginfo.msgmnb);
287 			printf("\tmsgtql: %6d\t(max # of messages in system)\n",
288 			    msginfo.msgtql);
289 			printf("\tmsgssz: %6d\t(size of a message segment)\n",
290 			    msginfo.msgssz);
291 			printf("\tmsgseg: %6d\t(# of message segments in system)\n\n",
292 			    msginfo.msgseg);
293 		}
294 		if (display & MSGINFO) {
295 			struct msqid_ds *xmsqids;
296 			size_t xmsqids_len;
297 
298 
299 			xmsqids_len = sizeof(struct msqid_ds) * msginfo.msgmni;
300 			xmsqids = malloc(xmsqids_len);
301 			kget(X_MSQIDS, xmsqids, xmsqids_len);
302 
303 			printf("Message Queues:\n");
304 			printf("T     ID     KEY        MODE       OWNER    GROUP");
305 			if (option & CREATOR)
306 				printf("  CREATOR   CGROUP");
307 			if (option & OUTSTANDING)
308 				printf(" CBYTES  QNUM");
309 			if (option & BIGGEST)
310 				printf(" QBYTES");
311 			if (option & PID)
312 				printf(" LSPID LRPID");
313 			if (option & TIME)
314 				printf("   STIME    RTIME    CTIME");
315 			printf("\n");
316 			for (i = 0; i < msginfo.msgmni; i += 1) {
317 				if (xmsqids[i].msg_qbytes != 0) {
318 					char    stime_buf[100], rtime_buf[100],
319 					        ctime_buf[100];
320 					struct msqid_ds *msqptr = &xmsqids[i];
321 
322 					cvt_time(msqptr->msg_stime, stime_buf);
323 					cvt_time(msqptr->msg_rtime, rtime_buf);
324 					cvt_time(msqptr->msg_ctime, ctime_buf);
325 
326 					printf("q %6d %10d %s %8s %8s",
327 					    IXSEQ_TO_IPCID(i, msqptr->msg_perm),
328 					    msqptr->msg_perm.key,
329 					    fmt_perm(msqptr->msg_perm.mode),
330 					    user_from_uid(msqptr->msg_perm.uid, 0),
331 					    group_from_gid(msqptr->msg_perm.gid, 0));
332 
333 					if (option & CREATOR)
334 						printf(" %8s %8s",
335 						    user_from_uid(msqptr->msg_perm.cuid, 0),
336 						    group_from_gid(msqptr->msg_perm.cgid, 0));
337 
338 					if (option & OUTSTANDING)
339 						printf(" %6d %6d",
340 						    msqptr->msg_cbytes,
341 						    msqptr->msg_qnum);
342 
343 					if (option & BIGGEST)
344 						printf(" %6d",
345 						    msqptr->msg_qbytes);
346 
347 					if (option & PID)
348 						printf(" %6d %6d",
349 						    msqptr->msg_lspid,
350 						    msqptr->msg_lrpid);
351 
352 					if (option & TIME)
353 						printf("%s %s %s",
354 						    stime_buf,
355 						    rtime_buf,
356 						    ctime_buf);
357 
358 					printf("\n");
359 				}
360 			}
361 			printf("\n");
362 		}
363 	} else
364 		if (display & (MSGINFO | MSGTOTAL)) {
365 			fprintf(stderr,
366 			    "SVID messages facility not configured in the system\n");
367 		}
368 
369 	kget(X_SHMINFO, &shminfo, sizeof(shminfo));
370 	if ((display & (SHMINFO | SHMTOTAL))) {
371 		if (display & SHMTOTAL) {
372 			printf("shminfo:\n");
373 			printf("\tshmmax: %7d\t(max shared memory segment size)\n",
374 			    shminfo.shmmax);
375 			printf("\tshmmin: %7d\t(min shared memory segment size)\n",
376 			    shminfo.shmmin);
377 			printf("\tshmmni: %7d\t(max number of shared memory identifiers)\n",
378 			    shminfo.shmmni);
379 			printf("\tshmseg: %7d\t(max shared memory segments per process)\n",
380 			    shminfo.shmseg);
381 			printf("\tshmall: %7d\t(max amount of shared memory in pages)\n\n",
382 			    shminfo.shmall);
383 		}
384 		if (display & SHMINFO) {
385 			struct shmid_ds *xshmids;
386 			size_t xshmids_len;
387 
388 			xshmids_len = sizeof(struct shmid_ds) * shminfo.shmmni;
389 			xshmids = malloc(xshmids_len);
390 			kget(X_SHMSEGS, xshmids, xshmids_len);
391 
392 			printf("Shared Memory:\n");
393 			printf("T     ID     KEY        MODE       OWNER    GROUP");
394 			if (option & CREATOR)
395 				printf("  CREATOR   CGROUP");
396 			if (option & OUTSTANDING)
397 				printf(" NATTCH");
398 			if (option & BIGGEST)
399 				printf("  SEGSZ");
400 			if (option & PID)
401 				printf("  CPID  LPID");
402 			if (option & TIME)
403 				printf("   ATIME    DTIME    CTIME");
404 			printf("\n");
405 			for (i = 0; i < shminfo.shmmni; i += 1) {
406 				if (xshmids[i].shm_perm.mode & 0x0800) {
407 					char    atime_buf[100], dtime_buf[100],
408 					        ctime_buf[100];
409 					struct shmid_ds *shmptr = &xshmids[i];
410 
411 					cvt_time(shmptr->shm_atime, atime_buf);
412 					cvt_time(shmptr->shm_dtime, dtime_buf);
413 					cvt_time(shmptr->shm_ctime, ctime_buf);
414 
415 					printf("m %6d %10d %s %8s %8s",
416 					    IXSEQ_TO_IPCID(i, shmptr->shm_perm),
417 					    shmptr->shm_perm.key,
418 					    fmt_perm(shmptr->shm_perm.mode),
419 					    user_from_uid(shmptr->shm_perm.uid, 0),
420 					    group_from_gid(shmptr->shm_perm.gid, 0));
421 
422 					if (option & CREATOR)
423 						printf(" %8s %8s",
424 						    user_from_uid(shmptr->shm_perm.cuid, 0),
425 						    group_from_gid(shmptr->shm_perm.cgid, 0));
426 
427 					if (option & OUTSTANDING)
428 						printf(" %6d",
429 						    shmptr->shm_nattch);
430 
431 					if (option & BIGGEST)
432 						printf(" %6d",
433 						    shmptr->shm_segsz);
434 
435 					if (option & PID)
436 						printf(" %6d %6d",
437 						    shmptr->shm_cpid,
438 						    shmptr->shm_lpid);
439 
440 					if (option & TIME)
441 						printf("%s %s %s",
442 						    atime_buf,
443 						    dtime_buf,
444 						    ctime_buf);
445 
446 					printf("\n");
447 				}
448 			}
449 			printf("\n");
450 		}
451 	} else
452 		if (display & (SHMINFO | SHMTOTAL)) {
453 			fprintf(stderr,
454 			    "SVID shared memory facility not configured in the system\n");
455 		}
456 
457 	kget(X_SEMINFO, &seminfo, sizeof(seminfo));
458 	if ((display & (SEMINFO | SEMTOTAL))) {
459 		struct semid_ds *xsema;
460 		size_t xsema_len;
461 
462 		if (display & SEMTOTAL) {
463 			printf("seminfo:\n");
464 			printf("\tsemmap: %6d\t(# of entries in semaphore map)\n",
465 			    seminfo.semmap);
466 			printf("\tsemmni: %6d\t(# of semaphore identifiers)\n",
467 			    seminfo.semmni);
468 			printf("\tsemmns: %6d\t(# of semaphores in system)\n",
469 			    seminfo.semmns);
470 			printf("\tsemmnu: %6d\t(# of undo structures in system)\n",
471 			    seminfo.semmnu);
472 			printf("\tsemmsl: %6d\t(max # of semaphores per id)\n",
473 			    seminfo.semmsl);
474 			printf("\tsemopm: %6d\t(max # of operations per semop call)\n",
475 			    seminfo.semopm);
476 			printf("\tsemume: %6d\t(max # of undo entries per process)\n",
477 			    seminfo.semume);
478 			printf("\tsemusz: %6d\t(size in bytes of undo structure)\n",
479 			    seminfo.semusz);
480 			printf("\tsemvmx: %6d\t(semaphore maximum value)\n",
481 			    seminfo.semvmx);
482 			printf("\tsemaem: %6d\t(adjust on exit max value)\n\n",
483 			    seminfo.semaem);
484 		}
485 		if (display & SEMINFO) {
486 			xsema_len = sizeof(struct semid_ds) * seminfo.semmni;
487 			xsema = malloc(xsema_len);
488 			kget(X_SEMA, xsema, xsema_len);
489 
490 			printf("Semaphores:\n");
491 			printf("T     ID     KEY        MODE       OWNER    GROUP");
492 			if (option & CREATOR)
493 				printf("  CREATOR   CGROUP");
494 			if (option & BIGGEST)
495 				printf(" NSEMS");
496 			if (option & TIME)
497 				printf("   OTIME    CTIME");
498 			printf("\n");
499 			for (i = 0; i < seminfo.semmni; i += 1) {
500 				if ((xsema[i].sem_perm.mode & SEM_ALLOC) != 0) {
501 					char    ctime_buf[100], otime_buf[100];
502 					struct semid_ds *semaptr = &xsema[i];
503 
504 					cvt_time(semaptr->sem_otime, otime_buf);
505 					cvt_time(semaptr->sem_ctime, ctime_buf);
506 
507 					printf("s %6d %10d %s %8s %8s",
508 					    IXSEQ_TO_IPCID(i, semaptr->sem_perm),
509 					    semaptr->sem_perm.key,
510 					    fmt_perm(semaptr->sem_perm.mode),
511 					    user_from_uid(semaptr->sem_perm.uid, 0),
512 					    group_from_gid(semaptr->sem_perm.gid, 0));
513 
514 					if (option & CREATOR)
515 						printf(" %8s %8s",
516 						    user_from_uid(semaptr->sem_perm.cuid, 0),
517 						    group_from_gid(semaptr->sem_perm.cgid, 0));
518 
519 					if (option & BIGGEST)
520 						printf(" %6d",
521 						    semaptr->sem_nsems);
522 
523 					if (option & TIME)
524 						printf("%s %s",
525 						    otime_buf,
526 						    ctime_buf);
527 
528 					printf("\n");
529 				}
530 			}
531 
532 			printf("\n");
533 		}
534 	} else
535 		if (display & (SEMINFO | SEMTOTAL)) {
536 			fprintf(stderr, "SVID semaphores facility not configured in the system\n");
537 		}
538 	if (!use_sysctl)
539 		kvm_close(kd);
540 
541 	exit(0);
542 }
543 
544 void
545 sysctlgatherstruct(addr, size, vecarr)
546 	void *addr;
547 	size_t size;
548 	struct scgs_vector *vecarr;
549 {
550 	struct scgs_vector *xp;
551 	size_t tsiz;
552 	int rv;
553 
554 	for (xp = vecarr; xp->sysctl != NULL; xp++) {
555 		assert(xp->offset <= size);
556 		tsiz = xp->size;
557 		rv = sysctlbyname(xp->sysctl, (char *)addr + xp->offset,
558 		    &tsiz, NULL, 0);
559 		if (rv == -1)
560 			errx(1, "sysctlbyname: %s", xp->sysctl);
561 		if (tsiz != xp->size)
562 			errx(1, "%s size mismatch (expected %d, got %d)",
563 			    xp->sysctl, xp->size, tsiz);
564 	}
565 }
566 
567 void
568 kget(idx, addr, size)
569 	int idx;
570 	void *addr;
571 	size_t size;
572 {
573 	char *symn;			/* symbol name */
574 	size_t tsiz;
575 	int rv;
576 	unsigned long kaddr;
577 	const char *sym2sysctl[] = {	/* symbol to sysctl name table */
578 		"kern.ipc.sema",
579 		"kern.ipc.seminfo",
580 		"kern.ipc.msginfo",
581 		"kern.ipc.msqids",
582 		"kern.ipc.shminfo",
583 		"kern.ipc.shmsegs" };
584 
585 	assert((unsigned)idx <= sizeof(sym2sysctl) / sizeof(*sym2sysctl));
586 	if (!use_sysctl) {
587 		symn = symbols[idx].n_name;
588 		if (*symn == '_')
589 			symn++;
590 		if (symbols[idx].n_type == 0 || symbols[idx].n_value == 0)
591 			errx(1, "symbol %s undefined", symn);
592 		/*
593 		 * For some symbols, the value we retreieve is
594 		 * actually a pointer; since we want the actual value,
595 		 * we have to manually dereference it.
596 		 */
597 		switch (idx) {
598 		case X_MSQIDS:
599 			tsiz = sizeof(msqids);
600 			rv = kvm_read(kd, symbols[idx].n_value,
601 			    &msqids, tsiz);
602 			kaddr = (u_long)msqids;
603 			break;
604 		case X_SHMSEGS:
605 			tsiz = sizeof(shmsegs);
606 			rv = kvm_read(kd, symbols[idx].n_value,
607 			    &shmsegs, tsiz);
608 			kaddr = (u_long)shmsegs;
609 			break;
610 		case X_SEMA:
611 			tsiz = sizeof(sema);
612 			rv = kvm_read(kd, symbols[idx].n_value,
613 			    &sema, tsiz);
614 			kaddr = (u_long)sema;
615 			break;
616 		default:
617 			rv = tsiz = 0;
618 			kaddr = symbols[idx].n_value;
619 			break;
620 		}
621 		if ((unsigned)rv != tsiz)
622 			errx(1, "%s: %s", symn, kvm_geterr(kd));
623 		if ((unsigned)kvm_read(kd, kaddr, addr, size) != size)
624 			errx(1, "%s: %s", symn, kvm_geterr(kd));
625 	} else {
626 		switch (idx) {
627 		case X_SHMINFO:
628 			sysctlgatherstruct(addr, size, shminfo_scgsv);
629 			break;
630 		case X_SEMINFO:
631 			sysctlgatherstruct(addr, size, seminfo_scgsv);
632 			break;
633 		case X_MSGINFO:
634 			sysctlgatherstruct(addr, size, msginfo_scgsv);
635 			break;
636 		default:
637 			tsiz = size;
638 			rv = sysctlbyname(sym2sysctl[idx], addr, &tsiz,
639 			    NULL, 0);
640 			if (rv == -1)
641 				err(1, "sysctlbyname: %s", sym2sysctl[idx]);
642 			if (tsiz != size)
643 				errx(1, "%s size mismatch "
644 				    "(expected %d, got %d)",
645 				    sym2sysctl[idx], size, tsiz);
646 			break;
647 		}
648 	}
649 }
650 
651 void
652 usage()
653 {
654 
655 	fprintf(stderr,
656 	    "usage: ipcs [-abcmopqsty] [-C corefile] [-N namelist]\n");
657 	exit(1);
658 }
659