xref: /minix/usr.bin/w/w.c (revision 83133719)
1 /*	$NetBSD: w.c,v 1.77 2013/09/09 19:20:38 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1980, 1991, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
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.
18  *
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
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1991, 1993, 1994\
35  The Regents of the University of California.  All rights reserved.");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)w.c	8.6 (Berkeley) 6/30/94";
41 #else
42 __RCSID("$NetBSD: w.c,v 1.77 2013/09/09 19:20:38 christos Exp $");
43 #endif
44 #endif /* not lint */
45 
46 /*
47  * w - print system status (who and what)
48  *
49  * This program is similar to the systat command on Tenex/Tops 10/20
50  *
51  */
52 #include <sys/param.h>
53 #include <sys/types.h>
54 #include <sys/time.h>
55 #include <sys/stat.h>
56 #include <sys/sysctl.h>
57 #include <sys/proc.h>
58 #include <sys/user.h>
59 #include <sys/ioctl.h>
60 #include <sys/socket.h>
61 
62 #include <netinet/in.h>
63 #include <arpa/inet.h>
64 
65 #include <ctype.h>
66 #include <err.h>
67 #include <errno.h>
68 #include <fcntl.h>
69 #include <kvm.h>
70 #include <limits.h>
71 #include <netdb.h>
72 #include <nlist.h>
73 #include <paths.h>
74 #include <stdio.h>
75 #include <stdlib.h>
76 #include <string.h>
77 #include <time.h>
78 #include <tzfile.h>
79 #include <unistd.h>
80 #ifdef SUPPORT_UTMP
81 #include <utmp.h>
82 #endif
83 #ifdef SUPPORT_UTMPX
84 #include <utmpx.h>
85 #endif
86 #include <vis.h>
87 
88 #include "extern.h"
89 
90 #ifdef __minix
91 /* MINIX3 note: please see this header for information about the port. */
92 #include "minix_proc.h"
93 #endif /* __minix */
94 
95 struct timeval	boottime;
96 struct winsize	ws;
97 kvm_t	       *kd;
98 time_t		now;		/* the current time of day */
99 int		ttywidth;	/* width of tty */
100 int		argwidth;	/* width of tty left to print process args */
101 int		header = 1;	/* true if -h flag: don't print heading */
102 int		nflag;		/* true if -n flag: don't convert addrs */
103 int		wflag;		/* true if -w flag: wide printout */
104 int		sortidle;	/* sort bu idle time */
105 char	       *sel_user;	/* login of particular user selected */
106 char		domain[MAXHOSTNAMELEN + 1];
107 int maxname = 8, maxline = 3, maxhost = 16;
108 
109 /*
110  * One of these per active utmp entry.
111  */
112 struct	entry {
113 	struct	entry *next;
114 	char name[UTX_USERSIZE + 1];
115 	char line[UTX_LINESIZE + 1];
116 	char host[UTX_HOSTSIZE + 1];
117 	char type[2];
118 	struct timeval tv;
119 	dev_t	tdev;			/* dev_t of terminal */
120 	time_t	idle;			/* idle time of terminal in seconds */
121 	struct	kinfo_proc2 *tp;	/* `most interesting' tty proc */
122 	struct	kinfo_proc2 *pp;	/* pid proc */
123 	pid_t	pid;			/* pid or ~0 if not known */
124 } *ehead = NULL, **nextp = &ehead;
125 
126 static void	pr_args(struct kinfo_proc2 *);
127 static void	pr_header(time_t *, int);
128 #ifndef __minix
129 static int	proc_compare_wrapper(const struct kinfo_proc2 *,
130     const struct kinfo_proc2 *);
131 #endif /* !__minix */
132 #if defined(SUPPORT_UTMP) || defined(SUPPORT_UTMPX)
133 static int	ttystat(const char *, struct stat *);
134 static void	process(struct entry *);
135 #endif
136 static void	fixhost(struct entry *ep);
137 __dead static void	usage(int);
138 
139 int
140 main(int argc, char **argv)
141 {
142 	struct kinfo_proc2 *kp;
143 	struct entry *ep;
144 	int ch, i, nentries, nusers, wcmd, curtain, use_sysctl;
145 	char *memf, *nlistf, *usrnp;
146 	const char *options;
147 	time_t then;
148 #ifndef __minix
149 	size_t len;
150 #endif /* !__minix */
151 #ifdef SUPPORT_UTMP
152 	struct utmp *ut;
153 #endif
154 #ifdef SUPPORT_UTMPX
155 	struct utmpx *utx;
156 #endif
157 	const char *progname;
158 #ifndef __minix
159 	char errbuf[_POSIX2_LINE_MAX];
160 #endif /* !__minix */
161 
162 	setprogname(argv[0]);
163 
164 	/* Are we w(1) or uptime(1)? */
165 	progname = getprogname();
166 	if (*progname == '-')
167 		progname++;
168 	if (*progname == 'u') {
169 		wcmd = 0;
170 		options = "";
171 	} else {
172 		wcmd = 1;
173 		options = "hiM:N:nw";
174 	}
175 
176 	memf = nlistf = NULL;
177 	while ((ch = getopt(argc, argv, options)) != -1)
178 		switch (ch) {
179 		case 'h':
180 			header = 0;
181 			break;
182 		case 'i':
183 			sortidle = 1;
184 			break;
185 		case 'M':
186 			header = 0;
187 			memf = optarg;
188 			break;
189 		case 'N':
190 			nlistf = optarg;
191 			break;
192 		case 'n':
193 			nflag = 1;
194 			break;
195 		case 'w':
196 			wflag = 1;
197 			break;
198 		case '?':
199 		default:
200 			usage(wcmd);
201 		}
202 	argc -= optind;
203 	argv += optind;
204 
205 	use_sysctl = (memf == NULL && nlistf == NULL);
206 
207 #ifndef __minix
208 	if ((kd = kvm_openfiles(nlistf, memf, NULL,
209 	    memf == NULL ? KVM_NO_FILES : O_RDONLY, errbuf)) == NULL)
210 		errx(1, "%s", errbuf);
211 #else
212 	if (!use_sysctl)
213 		errx(1, "The -M and -N flags are not supported on MINIX3.");
214 	kd = NULL;
215 #endif /* __minix */
216 
217 	(void)time(&now);
218 
219 	if (use_sysctl) {
220 #ifndef __minix
221 		len = sizeof(curtain);
222 		if (sysctlbyname("security.curtain", &curtain, &len,
223 		    NULL, 0) == -1)
224 #endif /* !__minix */
225 			curtain = 0;
226 	}
227 
228 #ifdef SUPPORT_UTMPX
229 	setutxent();
230 #endif
231 #ifdef SUPPORT_UTMP
232 	setutent();
233 #endif
234 
235 	if (*argv)
236 		sel_user = *argv;
237 
238 	nusers = 0;
239 #ifdef SUPPORT_UTMPX
240 	while ((utx = getutxent()) != NULL) {
241 		if (utx->ut_type != USER_PROCESS)
242 			continue;
243 		++nusers;
244 		if (sel_user &&
245 		    strncmp(utx->ut_name, sel_user, sizeof(utx->ut_name)) != 0)
246 			continue;
247 		if ((ep = calloc(1, sizeof(struct entry))) == NULL)
248 			err(1, NULL);
249 		(void)memcpy(ep->name, utx->ut_name, sizeof(utx->ut_name));
250 		(void)memcpy(ep->line, utx->ut_line, sizeof(utx->ut_line));
251 		ep->name[sizeof(utx->ut_name)] = '\0';
252 		ep->line[sizeof(utx->ut_line)] = '\0';
253 		if (!nflag || getnameinfo((struct sockaddr *)&utx->ut_ss,
254 		    utx->ut_ss.ss_len, ep->host, sizeof(ep->host), NULL, 0,
255 		    NI_NUMERICHOST) != 0) {
256 			(void)memcpy(ep->host, utx->ut_host,
257 			    sizeof(utx->ut_host));
258 			ep->host[sizeof(utx->ut_host)] = '\0';
259 		}
260 		fixhost(ep);
261 		ep->type[0] = 'x';
262 		ep->tv = utx->ut_tv;
263 		ep->pid = utx->ut_pid;
264 		*nextp = ep;
265 		nextp = &(ep->next);
266 		if (wcmd != 0)
267 			process(ep);
268 	}
269 #endif
270 
271 #ifdef SUPPORT_UTMP
272 	while ((ut = getutent()) != NULL) {
273 		if (ut->ut_name[0] == '\0')
274 			continue;
275 
276 		if (sel_user &&
277 		    strncmp(ut->ut_name, sel_user, sizeof(ut->ut_name)) != 0)
278 			continue;
279 
280 		/* Don't process entries that we have utmpx for */
281 		for (ep = ehead; ep != NULL; ep = ep->next) {
282 			if (strncmp(ep->line, ut->ut_line,
283 			    sizeof(ut->ut_line)) == 0)
284 				break;
285 		}
286 		if (ep != NULL)
287 			continue;
288 
289 		++nusers;
290 		if ((ep = calloc(1, sizeof(struct entry))) == NULL)
291 			err(1, NULL);
292 		(void)memcpy(ep->name, ut->ut_name, sizeof(ut->ut_name));
293 		(void)memcpy(ep->line, ut->ut_line, sizeof(ut->ut_line));
294 		(void)memcpy(ep->host, ut->ut_host, sizeof(ut->ut_host));
295 		ep->name[sizeof(ut->ut_name)] = '\0';
296 		ep->line[sizeof(ut->ut_line)] = '\0';
297 		ep->host[sizeof(ut->ut_host)] = '\0';
298 		fixhost(ep);
299 		ep->tv.tv_sec = ut->ut_time;
300 		*nextp = ep;
301 		nextp = &(ep->next);
302 		if (wcmd != 0)
303 			process(ep);
304 	}
305 #endif
306 
307 #ifdef SUPPORT_UTMPX
308 	endutxent();
309 #endif
310 #ifdef SUPPORT_UTMP
311 	endutent();
312 #endif
313 
314 	if (header || wcmd == 0) {
315 		pr_header(&now, nusers);
316 		if (wcmd == 0)
317 			exit (0);
318 	}
319 
320 	if ((kp = kvm_getproc2(kd, KERN_PROC_ALL, 0,
321 	    sizeof(struct kinfo_proc2), &nentries)) == NULL)
322 		errx(1, "%s", kvm_geterr(kd));
323 
324 	/* Include trailing space because TTY header starts one column early. */
325 	for (i = 0; i < nentries; i++, kp++) {
326 
327 		for (ep = ehead; ep != NULL; ep = ep->next) {
328 			if (ep->tdev != 0 && ep->tdev == kp->p_tdev &&
329 			    kp->p__pgid == kp->p_tpgid) {
330 				/*
331 				 * Proc is in foreground of this
332 				 * terminal
333 				 */
334 				if (proc_compare_wrapper(ep->tp, kp))
335 					ep->tp = kp;
336 				break;
337 			}
338 			if (ep->pid != 0 && ep->pid == kp->p_pid) {
339 				ep->pp = kp;
340 				break;
341 			}
342 		}
343 	}
344 
345 	if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 &&
346 	    ioctl(STDERR_FILENO, TIOCGWINSZ, &ws) == -1 &&
347 	    ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == -1) || ws.ws_col == 0)
348 		ttywidth = 79;
349 	else
350 		ttywidth = ws.ws_col - 1;
351 
352 	if (!wflag && maxhost > (ttywidth / 3))
353 		maxhost = ttywidth / 3;
354 
355 	argwidth = printf("%-*s TTY     %-*s %*s  IDLE WHAT\n",
356 	    maxname, "USER", maxhost, "FROM",
357 	    7 /* "dddhhXm" */, "LOGIN@");
358 	argwidth -= sizeof("WHAT\n") - 1 /* NUL */;
359 	argwidth = ttywidth - argwidth;
360 	if (argwidth < 4)
361 		argwidth = 8;
362 	if (wflag)
363 		argwidth = -1;
364 
365 	/* sort by idle time */
366 	if (sortidle && ehead != NULL) {
367 		struct entry *from = ehead, *save;
368 
369 		ehead = NULL;
370 		while (from != NULL) {
371 			for (nextp = &ehead;
372 			    (*nextp) && from->idle >= (*nextp)->idle;
373 			    nextp = &(*nextp)->next)
374 				continue;
375 			save = from;
376 			from = from->next;
377 			save->next = *nextp;
378 			*nextp = save;
379 		}
380 	}
381 #if defined(SUPPORT_UTMP) && defined(SUPPORT_UTMPX)
382 	else if (ehead != NULL) {
383 		struct entry *from = ehead, *save;
384 
385 		ehead = NULL;
386 		while (from != NULL) {
387 			for (nextp = &ehead;
388 			    (*nextp) && strcmp(from->line, (*nextp)->line) > 0;
389 			    nextp = &(*nextp)->next)
390 				continue;
391 			save = from;
392 			from = from->next;
393 			save->next = *nextp;
394 			*nextp = save;
395 		}
396 	}
397 #endif
398 
399 	if (!nflag) {
400 		int	rv;
401 		char	*p;
402 
403 		rv = gethostname(domain, sizeof(domain));
404 		domain[sizeof(domain) - 1] = '\0';
405 		if (rv < 0 || (p = strchr(domain, '.')) == 0)
406 			domain[0] = '\0';
407 		else
408 			memmove(domain, p, strlen(p) + 1);
409 	}
410 
411 	for (ep = ehead; ep != NULL; ep = ep->next) {
412 		if (ep->tp != NULL)
413 			kp = ep->tp;
414 		else if (ep->pp != NULL)
415 			kp = ep->pp;
416 		else if (ep->pid != 0) {
417 			if (curtain)
418 				kp = NULL;
419 			else {
420 				warnx("Stale utmp%s entry: %s %s %s",
421 				    ep->type, ep->name, ep->line, ep->host);
422 				continue;
423 			}
424 		}
425 #ifndef __minix
426 		usrnp = (kp == NULL) ? ep->name : kp->p_login;
427 #else
428 		usrnp = ep->name; /* TODO: implement getlogin/setlogin */
429 #endif /* __minix */
430 		(void)printf("%-*s %-7.7s %-*.*s ",
431 		    maxname, usrnp, ep->line,
432 		    maxhost, maxhost, ep->host);
433 		then = (time_t)ep->tv.tv_sec;
434 		pr_attime(&then, &now);
435 		pr_idle(ep->idle);
436 		pr_args(kp);
437 		(void)printf("\n");
438 	}
439 	exit(0);
440 }
441 
442 static void
443 pr_args(struct kinfo_proc2 *kp)
444 {
445 	char **argv;
446 	int left;
447 
448 	if (kp == 0)
449 		goto nothing;
450 	left = argwidth;
451 	argv = kvm_getargv2(kd, kp, (argwidth < 0) ? 0 : argwidth);
452 	if (argv == 0) {
453 		if (kp->p_comm == 0) {
454 			goto nothing;
455 		} else {
456 			fmt_putc('(', &left);
457 			fmt_puts((char *)kp->p_comm, &left);
458 			fmt_putc(')', &left);
459 			return;
460 		}
461 	}
462 	while (*argv) {
463 		fmt_puts(*argv, &left);
464 		argv++;
465 		fmt_putc(' ', &left);
466 	}
467 	return;
468 nothing:
469 	putchar('-');
470 }
471 
472 static void
473 pr_header(time_t *nowp, int nusers)
474 {
475 	double avenrun[3];
476 	time_t uptime;
477 	int days, hrs, mins;
478 #ifndef __minix
479 	int mib[2];
480 	size_t size, i;
481 #else
482 	size_t i;
483 #endif /* __minix */
484 	char buf[256];
485 
486 	/*
487 	 * Print time of day.
488 	 *
489 	 * SCCS forces the string manipulation below, as it replaces
490 	 * %, M, and % in a character string with the file name.
491 	 */
492 	(void)strftime(buf, sizeof(buf), "%l:%" "M%p", localtime(nowp));
493 	buf[sizeof(buf) - 1] = '\0';
494 	(void)printf("%s ", buf);
495 
496 	/*
497 	 * Print how long system has been up.
498 	 * (Found by looking getting "boottime" from the kernel)
499 	 */
500 #ifndef __minix
501 	mib[0] = CTL_KERN;
502 	mib[1] = KERN_BOOTTIME;
503 	size = sizeof(boottime);
504 	if (sysctl(mib, 2, &boottime, &size, NULL, 0) != -1 &&
505 	    boottime.tv_sec != 0) {
506 		uptime = now - boottime.tv_sec;
507 #else
508 	if (minix_getuptime(&uptime) != -1) {
509 #endif /* __minix */
510 		uptime += 30;
511 		if (uptime > SECSPERMIN) {
512 			days = uptime / SECSPERDAY;
513 			uptime %= SECSPERDAY;
514 			hrs = uptime / SECSPERHOUR;
515 			uptime %= SECSPERHOUR;
516 			mins = uptime / SECSPERMIN;
517 			(void)printf(" up");
518 			if (days > 0)
519 				(void)printf(" %d day%s,", days,
520 				    days > 1 ? "s" : "");
521 			if (hrs > 0 && mins > 0)
522 				(void)printf(" %2d:%02d,", hrs, mins);
523 			else {
524 				if (hrs > 0)
525 					(void)printf(" %d hr%s,",
526 					    hrs, hrs > 1 ? "s" : "");
527 				if (mins > 0)
528 					(void)printf(" %d min%s,",
529 					    mins, mins > 1 ? "s" : "");
530 			}
531 		}
532 	}
533 
534 	/* Print number of users logged in to system */
535 	(void)printf(" %d user%s", nusers, nusers != 1 ? "s" : "");
536 
537 	/*
538 	 * Print 1, 5, and 15 minute load averages.
539 	 */
540 	if (getloadavg(avenrun, sizeof(avenrun) / sizeof(avenrun[0])) == -1)
541 		(void)printf(", no load average information available\n");
542 	else {
543 		(void)printf(", load averages:");
544 		for (i = 0; i < (sizeof(avenrun) / sizeof(avenrun[0])); i++) {
545 			if (i > 0)
546 				(void)printf(",");
547 			(void)printf(" %.2f", avenrun[i]);
548 		}
549 		(void)printf("\n");
550 	}
551 }
552 
553 #if defined(SUPPORT_UTMP) || defined(SUPPORT_UTMPX)
554 static int
555 ttystat(const char *line, struct stat *st)
556 {
557 	char ttybuf[MAXPATHLEN];
558 
559 	(void)snprintf(ttybuf, sizeof(ttybuf), "%s%s", _PATH_DEV, line);
560 	return stat(ttybuf, st);
561 }
562 
563 static void
564 process(struct entry *ep)
565 {
566 	struct stat st;
567 	time_t touched;
568 	int max;
569 
570 	if ((max = strlen(ep->name)) > maxname)
571 		maxname = max;
572 	if ((max = strlen(ep->line)) > maxline)
573 		maxline = max;
574 	if ((max = strlen(ep->host)) > maxhost)
575 		maxhost = max;
576 
577 	ep->tdev = 0;
578 	ep->idle = (time_t)-1;
579 
580 #ifdef SUPPORT_UTMP
581 	/*
582 	 * Hack to recognize and correctly parse
583 	 * ut entry made by ftpd. The "tty" used
584 	 * by ftpd is not a real tty, just identifier in
585 	 * form ftpPID. Pid parsed from the "tty name"
586 	 * is used later to match corresponding process.
587 	 * NB: This is only used for utmp entries. For utmpx,
588 	 * we already have the pid.
589 	 */
590 	if (ep->pid == 0 && strncmp(ep->line, "ftp", 3) == 0) {
591 		ep->pid = strtol(ep->line + 3, NULL, 10);
592 		return;
593 	}
594 #endif
595 	if (ttystat(ep->line, &st) == -1)
596 		return;
597 
598 	ep->tdev = st.st_rdev;
599 	/*
600 	 * If this is the console device, attempt to ascertain
601 	 * the true console device dev_t.
602 	 */
603 	if (ep->tdev == 0) {
604 		int mib[2];
605 		size_t size;
606 
607 		mib[0] = CTL_KERN;
608 		mib[1] = KERN_CONSDEV;
609 		size = sizeof(dev_t);
610 		(void) sysctl(mib, 2, &ep->tdev, &size, NULL, 0);
611 	}
612 
613 	touched = st.st_atime;
614 	if (touched < ep->tv.tv_sec) {
615 		/* tty untouched since before login */
616 		touched = ep->tv.tv_sec;
617 	}
618 	if ((ep->idle = now - touched) < 0)
619 		ep->idle = 0;
620 }
621 #endif
622 
623 #ifndef __minix
624 static int
625 proc_compare_wrapper(const struct kinfo_proc2 *p1,
626     const struct kinfo_proc2 *p2)
627 {
628 	struct kinfo_lwp *l1, *l2;
629 	int cnt;
630 
631 	if (p1 == NULL)
632 		return 1;
633 
634 	l1 = kvm_getlwps(kd, p1->p_pid, 0, sizeof(*l1), &cnt);
635 	if (l1 == NULL || cnt == 0)
636 		return 1;
637 
638 	l2 = kvm_getlwps(kd, p2->p_pid, 0, sizeof(*l1), &cnt);
639 	if (l2 == NULL || cnt == 0)
640 		return 0;
641 
642 	return proc_compare(p1, l1, p2, l2);
643 }
644 #endif /* !__minix */
645 
646 static void
647 fixhost(struct entry *ep)
648 {
649 	char host_buf[sizeof(ep->host)];
650 	char *p, *x;
651 	struct hostent *hp;
652 	struct in_addr l;
653 
654 	strlcpy(host_buf, *ep->host ? ep->host : "-", sizeof(host_buf));
655 	p = host_buf;
656 
657 	/*
658 	 * XXX: Historical behavior, ':' in hostname means X display number,
659 	 * IPv6 not handled.
660 	 */
661 	for (x = p; x < &host_buf[sizeof(host_buf)]; x++)
662 		if (*x == '\0' || *x == ':')
663 			break;
664 	if (x == p + sizeof(host_buf) || *x != ':')
665 		x = NULL;
666 	else
667 		*x++ = '\0';
668 
669 	if (!nflag && inet_aton(p, &l) &&
670 	    (hp = gethostbyaddr((char *)&l, sizeof(l), AF_INET))) {
671 		if (domain[0] != '\0') {
672 			p = hp->h_name;
673 			p += strlen(hp->h_name);
674 			p -= strlen(domain);
675 			if (p > hp->h_name &&
676 			    strcasecmp(p, domain) == 0)
677 				*p = '\0';
678 		}
679 		p = hp->h_name;
680 	}
681 
682 	if (x)
683 		(void)snprintf(ep->host, sizeof(ep->host), "%s:%s", p, x);
684 	else
685 
686 		strlcpy(ep->host, p, sizeof(ep->host));
687 }
688 
689 static void
690 usage(int wcmd)
691 {
692 
693 	if (wcmd)
694 		(void)fprintf(stderr,
695 		    "Usage: %s [-hinw] [-M core] [-N system] [user]\n",
696 		    getprogname());
697 	else
698 		(void)fprintf(stderr, "Usage: %s\n", getprogname());
699 	exit(1);
700 }
701