xref: /netbsd-src/usr.bin/man/man.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*
2  * Copyright (c) 1987, 1993, 1994
3  *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static char copyright[] =
36 "@(#) Copyright (c) 1987, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 static char sccsid[] = "@(#)man.c	8.13 (Berkeley) 12/20/93";
42 #endif /* not lint */
43 
44 #include <sys/param.h>
45 #include <sys/queue.h>
46 
47 #include <ctype.h>
48 #include <err.h>
49 #include <errno.h>
50 #include <fcntl.h>
51 #include <fnmatch.h>
52 #include <glob.h>
53 #include <signal.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 
59 #include "config.h"
60 #include "pathnames.h"
61 
62 int f_all, f_where;
63 
64 static void	 build_page __P((char *, char **));
65 static void	 cat __P((char *));
66 static char	*check_pager __P((char *));
67 static int	 cleanup __P((void));
68 static void	 how __P((char *));
69 static void	 jump __P((char **, char *, char *));
70 static int	 manual __P((char *, TAG *, glob_t *));
71 static void	 onsig __P((int));
72 static void	 usage __P((void));
73 
74 int
75 main(argc, argv)
76 	int argc;
77 	char *argv[];
78 {
79 	extern char *optarg;
80 	extern int optind;
81 	TAG *defp, *defnewp, *section, *sectnewp, *subp;
82 	ENTRY *e_defp, *e_sectp, *e_subp, *ep;
83 	glob_t pg;
84 	size_t len;
85 	int ch, f_cat, f_how, found;
86 	char **ap, *cmd, *machine, *p, *p_add, *p_path, *pager, *slashp;
87 	char *conffile, buf[MAXPATHLEN * 2];
88 
89 	f_cat = f_how = 0;
90 	conffile = p_add = p_path = NULL;
91 	while ((ch = getopt(argc, argv, "-aC:cfhkM:m:P:w")) != EOF)
92 		switch (ch) {
93 		case 'a':
94 			f_all = 1;
95 			break;
96 		case 'C':
97 			conffile = optarg;
98 			break;
99 		case 'c':
100 		case '-':		/* Deprecated. */
101 			f_cat = 1;
102 			break;
103 		case 'h':
104 			f_how = 1;
105 			break;
106 		case 'm':
107 			p_add = optarg;
108 			break;
109 		case 'M':
110 		case 'P':		/* Backward compatibility. */
111 			p_path = optarg;
112 			break;
113 		/*
114 		 * The -f and -k options are backward compatible,
115 		 * undocumented ways of calling whatis(1) and apropos(1).
116 		 */
117 		case 'f':
118 			jump(argv, "-f", "whatis");
119 			/* NOTREACHED */
120 		case 'k':
121 			jump(argv, "-k", "apropos");
122 			/* NOTREACHED */
123 		case 'w':
124 			f_all = f_where = 1;
125 			break;
126 		case '?':
127 		default:
128 			usage();
129 		}
130 	argc -= optind;
131 	argv += optind;
132 
133 	if (!*argv)
134 		usage();
135 
136 	if (!f_cat && !f_how && !f_where)
137 		if (!isatty(1))
138 			f_cat = 1;
139 		else if ((pager = getenv("PAGER")) != NULL)
140 			pager = check_pager(pager);
141 		else
142 			pager = _PATH_PAGER;
143 
144 	/* Read the configuration file. */
145 	config(conffile);
146 
147 	/* Get the machine type. */
148 	if ((machine = getenv("MACHINE")) == NULL)
149 		machine = MACHINE;
150 
151 	/* If there's no _default list, create an empty one. */
152 	if ((defp = getlist("_default")) == NULL)
153 		defp = addlist("_default");
154 
155 	/*
156 	 * 1: If the user specified a MANPATH variable, or set the -M
157 	 *    option, we replace the _default list with the user's list,
158 	 *    appending the entries in the _subdir list and the machine.
159 	 */
160 	if (p_path == NULL)
161 		p_path = getenv("MANPATH");
162 	if (p_path != NULL) {
163 		while ((e_defp = defp->list.tqh_first) != NULL) {
164 			free(e_defp->s);
165 			TAILQ_REMOVE(&defp->list, e_defp, q);
166 		}
167 		for (p = strtok(p_path, ":");
168 		    p != NULL; p = strtok(NULL, ":")) {
169 			slashp = p[strlen(p) - 1] == '/' ? "" : "/";
170 			e_subp = (subp = getlist("_subdir")) == NULL ?
171 			    NULL : subp->list.tqh_first;
172 			for (; e_subp != NULL; e_subp = e_subp->q.tqe_next) {
173 				(void)snprintf(buf, sizeof(buf), "%s%s%s{/%s,}",
174 				    p, slashp, e_subp->s, machine);
175 				if ((ep = malloc(sizeof(ENTRY))) == NULL ||
176 				    (ep->s = strdup(buf)) == NULL)
177 					err(1, NULL);
178 				TAILQ_INSERT_TAIL(&defp->list, ep, q);
179 			}
180 		}
181 	}
182 
183 	/*
184 	 * 2: If the user did not specify MANPATH, -M or a section, rewrite
185 	 *    the _default list to include the _subdir list and the machine.
186 	 */
187 	if (argv[1] == NULL)
188 		section = NULL;
189 	else if ((section = getlist(*argv)) != NULL)
190 		++argv;
191 	if (p_path == NULL && section == NULL) {
192 		defnewp = addlist("_default_new");
193 		e_defp =
194 		    defp->list.tqh_first == NULL ? NULL : defp->list.tqh_first;
195 		for (; e_defp != NULL; e_defp = e_defp->q.tqe_next) {
196 			slashp =
197 			    e_defp->s[strlen(e_defp->s) - 1] == '/' ? "" : "/";
198 			e_subp = (subp = getlist("_subdir")) == NULL ?
199 			    NULL : subp->list.tqh_first;
200 			for (; e_subp != NULL; e_subp = e_subp->q.tqe_next) {
201 				(void)snprintf(buf, sizeof(buf), "%s%s%s{/%s,}",
202 				e_defp->s, slashp, e_subp->s, machine);
203 				if ((ep = malloc(sizeof(ENTRY))) == NULL ||
204 				    (ep->s = strdup(buf)) == NULL)
205 					err(1, NULL);
206 				TAILQ_INSERT_TAIL(&defnewp->list, ep, q);
207 			}
208 		}
209 		defp = getlist("_default");
210 		while ((e_defp = defp->list.tqh_first) != NULL) {
211 			free(e_defp->s);
212 			TAILQ_REMOVE(&defp->list, e_defp, q);
213 		}
214 		free(defp->s);
215 		TAILQ_REMOVE(&head, defp, q);
216 		defnewp = getlist("_default_new");
217 		free(defnewp->s);
218 		defnewp->s = "_default";
219 		defp = defnewp;
220 	}
221 
222 	/*
223 	 * 3: If the user set the -m option, insert the user's list before
224 	 *    whatever list we have, again appending the _subdir list and
225 	 *    the machine.
226 	 */
227 	if (p_add != NULL)
228 		for (p = strtok(p_add, ":"); p != NULL; p = strtok(NULL, ":")) {
229 			slashp = p[strlen(p) - 1] == '/' ? "" : "/";
230 			e_subp = (subp = getlist("_subdir")) == NULL ?
231 			    NULL : subp->list.tqh_first;
232 			for (; e_subp != NULL; e_subp = e_subp->q.tqe_next) {
233 				(void)snprintf(buf, sizeof(buf), "%s%s%s{/%s,}",
234 				    p, slashp, e_subp->s, machine);
235 				if ((ep = malloc(sizeof(ENTRY))) == NULL ||
236 				    (ep->s = strdup(buf)) == NULL)
237 					err(1, NULL);
238 				TAILQ_INSERT_HEAD(&defp->list, ep, q);
239 			}
240 		}
241 
242 	/*
243 	 * 4: If none of MANPATH, -M, or -m were specified, and a section was,
244 	 *    rewrite the section's paths (if they have a trailing slash) to
245 	 *    append the _subdir list and the machine.  This then becomes the
246 	 *    _default list.
247 	 */
248 	if (p_path == NULL && p_add == NULL && section != NULL) {
249 		sectnewp = addlist("_section_new");
250 		for (e_sectp = section->list.tqh_first;
251 		    e_sectp != NULL; e_sectp = e_sectp->q.tqe_next) {
252 			if (e_sectp->s[strlen(e_sectp->s) - 1] != '/') {
253 				(void)snprintf(buf, sizeof(buf),
254 				    "%s{/%s,}", e_sectp->s, machine);
255 				if ((ep = malloc(sizeof(ENTRY))) == NULL ||
256 				    (ep->s = strdup(buf)) == NULL)
257 					err(1, NULL);
258 				TAILQ_INSERT_TAIL(&sectnewp->list, ep, q);
259 				continue;
260 			}
261 			e_subp = (subp = getlist("_subdir")) == NULL ?
262 			    NULL : subp->list.tqh_first;
263 			for (; e_subp != NULL; e_subp = e_subp->q.tqe_next) {
264 				(void)snprintf(buf, sizeof(buf), "%s%s{/%s,}",
265 				    e_sectp->s, e_subp->s, machine);
266 				if ((ep = malloc(sizeof(ENTRY))) == NULL ||
267 				    (ep->s = strdup(buf)) == NULL)
268 					err(1, NULL);
269 				TAILQ_INSERT_TAIL(&sectnewp->list, ep, q);
270 			}
271 		}
272 		sectnewp->s = section->s;
273 		defp = sectnewp;
274 		TAILQ_REMOVE(&head, section, q);
275 	}
276 
277 	/*
278 	 * 5: Search for the files.  Set up an interrupt handler, so the
279 	 *    temporary files go away.
280 	 */
281 	(void)signal(SIGINT, onsig);
282 	(void)signal(SIGHUP, onsig);
283 
284 	memset(&pg, 0, sizeof(pg));
285 	for (found = 0; *argv; ++argv)
286 		if (manual(*argv, defp, &pg))
287 			found = 1;
288 
289 	/* 6: If nothing found, we're done. */
290 	if (!found) {
291 		(void)cleanup();
292 		exit (1);
293 	}
294 
295 	/* 7: If it's simple, display it fast. */
296 	if (f_cat) {
297 		for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
298 			if (**ap == '\0')
299 				continue;
300 			cat(*ap);
301 		}
302 		exit (cleanup());
303 	}
304 	if (f_how) {
305 		for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
306 			if (**ap == '\0')
307 				continue;
308 			how(*ap);
309 		}
310 		exit(cleanup());
311 	}
312 	if (f_where) {
313 		for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
314 			if (**ap == '\0')
315 				continue;
316 			(void)printf("%s\n", *ap);
317 		}
318 		exit(cleanup());
319 	}
320 
321 	/*
322 	 * 8: We display things in a single command; build a list of things
323 	 *    to display.
324 	 */
325 	for (ap = pg.gl_pathv, len = strlen(pager) + 1; *ap != NULL; ++ap) {
326 		if (**ap == '\0')
327 			continue;
328 		len += strlen(*ap) + 1;
329 	}
330 	if ((cmd = malloc(len)) == NULL) {
331 		warn(NULL);
332 		(void)cleanup();
333 		exit(1);
334 	}
335 	p = cmd;
336 	len = strlen(pager);
337 	memmove(p, pager, len);
338 	p += len;
339 	*p++ = ' ';
340 	for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
341 		if (**ap == '\0')
342 			continue;
343 		len = strlen(*ap);
344 		memmove(p, *ap, len);
345 		p += len;
346 		*p++ = ' ';
347 	}
348 	*p = '\0';
349 
350 	/* Use system(3) in case someone's pager is "pager arg1 arg2". */
351 	(void)system(cmd);
352 
353 	exit(cleanup());
354 }
355 
356 /*
357  * manual --
358  *	Search the manuals for the pages.
359  */
360 static int
361 manual(page, tag, pg)
362 	char *page;
363 	TAG *tag;
364 	glob_t *pg;
365 {
366 	ENTRY *ep, *e_sufp, *e_tag;
367 	TAG *missp, *sufp;
368 	int anyfound, cnt, found;
369 	char *p, buf[128];
370 
371 	anyfound = 0;
372 	buf[0] = '*';
373 
374 	/* For each element in the list... */
375 	e_tag = tag == NULL ? NULL : tag->list.tqh_first;
376 	for (; e_tag != NULL; e_tag = e_tag->q.tqe_next) {
377 		(void)snprintf(buf, sizeof(buf), "%s/%s.*", e_tag->s, page);
378 		if (glob(buf,
379 		    GLOB_APPEND | GLOB_BRACE | GLOB_NOSORT | GLOB_QUOTE,
380 		    NULL, pg)) {
381 			warn("globbing");
382 			(void)cleanup();
383 			exit(1);
384 		}
385 		if (pg->gl_matchc == 0)
386 			continue;
387 
388 		/* Find out if it's really a man page. */
389 		for (cnt = pg->gl_pathc - pg->gl_matchc;
390 		    cnt < pg->gl_pathc; ++cnt) {
391 
392 			/*
393 			 * Try the _suffix key words first.
394 			 *
395 			 * XXX
396 			 * Older versions of man.conf didn't have the suffix
397 			 * key words, it was assumed that everything was a .0.
398 			 * We just test for .0 first, it's fast and probably
399 			 * going to hit.
400 			 */
401 			(void)snprintf(buf, sizeof(buf), "*/%s.0", page);
402 			if (!fnmatch(buf, pg->gl_pathv[cnt], 0))
403 				goto next;
404 
405 			e_sufp = (sufp = getlist("_suffix")) == NULL ?
406 			    NULL : sufp->list.tqh_first;
407 			for (found = 0;
408 			    e_sufp != NULL; e_sufp = e_sufp->q.tqe_next) {
409 				(void)snprintf(buf,
410 				     sizeof(buf), "*/%s%s", page, e_sufp->s);
411 				if (!fnmatch(buf, pg->gl_pathv[cnt], 0)) {
412 					found = 1;
413 					break;
414 				}
415 			}
416 			if (found)
417 				goto next;
418 
419 			/* Try the _build key words next. */
420 			e_sufp = (sufp = getlist("_build")) == NULL ?
421 			    NULL : sufp->list.tqh_first;
422 			for (found = 0;
423 			    e_sufp != NULL; e_sufp = e_sufp->q.tqe_next) {
424 				for (p = e_sufp->s;
425 				    *p != '\0' && !isspace(*p); ++p);
426 				if (*p == '\0')
427 					continue;
428 				*p = '\0';
429 				(void)snprintf(buf,
430 				     sizeof(buf), "*/%s%s", page, e_sufp->s);
431 				if (!fnmatch(buf, pg->gl_pathv[cnt], 0)) {
432 					if (!f_where)
433 						build_page(p + 1,
434 						    &pg->gl_pathv[cnt]);
435 					*p = ' ';
436 					found = 1;
437 					break;
438 				}
439 				*p = ' ';
440 			}
441 			if (found) {
442 next:				anyfound = 1;
443 				if (!f_all) {
444 					/* Delete any other matches. */
445 					while (++cnt< pg->gl_pathc)
446 						pg->gl_pathv[cnt] = "";
447 					break;
448 				}
449 				continue;
450 			}
451 
452 			/* It's not a man page, forget about it. */
453 			pg->gl_pathv[cnt] = "";
454 		}
455 
456 		if (anyfound && !f_all)
457 			break;
458 	}
459 
460 	/* If not found, enter onto the missing list. */
461 	if (!anyfound) {
462 		if ((missp = getlist("_missing")) == NULL)
463 			missp = addlist("_missing");
464 		if ((ep = malloc(sizeof(ENTRY))) == NULL ||
465 		    (ep->s = strdup(page)) == NULL) {
466 			warn(NULL);
467 			(void)cleanup();
468 			exit(1);
469 		}
470 		TAILQ_INSERT_TAIL(&missp->list, ep, q);
471 	}
472 	return (anyfound);
473 }
474 
475 /*
476  * build_page --
477  *	Build a man page for display.
478  */
479 static void
480 build_page(fmt, pathp)
481 	char *fmt, **pathp;
482 {
483 	static int warned;
484 	ENTRY *ep;
485 	TAG *intmpp;
486 	int fd, n;
487 	char *p, *b;
488 	char buf[MAXPATHLEN], cmd[MAXPATHLEN], tpath[sizeof(_PATH_TMP)];
489 
490 	/* Let the user know this may take awhile. */
491 	if (!warned) {
492 		warned = 1;
493 		warnx("Formatting manual page...");
494 	}
495 
496 	/*
497 	 * Historically man chdir'd to the root of the man tree.
498 	 * This was used in man pages that contained relative ".so"
499 	 * directives (including other man pages for command aliases etc.)
500 	 * It even went one step farther, by examining the first line
501 	 * of the man page and parsing the .so filename so it would
502 	 * make hard(?) links to the cat'ted man pages for space savings.
503 	 * (We don't do that here, but we could).
504 	 */
505 
506 	/* copy and find the end */
507 	for (b = buf, p = *pathp; (*b++ = *p++) != '\0';)
508 		continue;
509 
510 	/* skip the last two path components, page name and man[n] */
511 	for (--b, n = 2; b != buf; b--)
512 		if (*b == '/')
513 			if (--n == 0) {
514 				*b = '\0';
515 				(void) chdir(buf);
516 			}
517 
518 	/* Add a remove-when-done list. */
519 	if ((intmpp = getlist("_intmp")) == NULL)
520 		intmpp = addlist("_intmp");
521 
522 	/* Move to the printf(3) format string. */
523 	for (; *fmt && isspace(*fmt); ++fmt)
524 		continue;
525 
526 	/*
527 	 * Get a temporary file and build a version of the file
528 	 * to display.  Replace the old file name with the new one.
529 	 */
530 	(void)strcpy(tpath, _PATH_TMP);
531 	if ((fd = mkstemp(tpath)) == -1) {
532 		warn("%s", tpath);
533 		(void)cleanup();
534 		exit(1);
535 	}
536 	(void)snprintf(buf, sizeof(buf), "%s > %s", fmt, tpath);
537 	(void)snprintf(cmd, sizeof(cmd), buf, *pathp);
538 	(void)system(cmd);
539 	(void)close(fd);
540 	if ((*pathp = strdup(tpath)) == NULL) {
541 		warn(NULL);
542 		(void)cleanup();
543 		exit(1);
544 	}
545 
546 	/* Link the built file into the remove-when-done list. */
547 	if ((ep = malloc(sizeof(ENTRY))) == NULL) {
548 		warn(NULL);
549 		(void)cleanup();
550 		exit(1);
551 	}
552 	ep->s = *pathp;
553 	TAILQ_INSERT_TAIL(&intmpp->list, ep, q);
554 }
555 
556 /*
557  * how --
558  *	display how information
559  */
560 static void
561 how(fname)
562 	char *fname;
563 {
564 	FILE *fp;
565 
566 	int lcnt, print;
567 	char *p, buf[256];
568 
569 	if (!(fp = fopen(fname, "r"))) {
570 		warn("%s", fname);
571 		(void)cleanup();
572 		exit (1);
573 	}
574 #define	S1	"SYNOPSIS"
575 #define	S2	"S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS"
576 #define	D1	"DESCRIPTION"
577 #define	D2	"D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN"
578 	for (lcnt = print = 0; fgets(buf, sizeof(buf), fp);) {
579 		if (!strncmp(buf, S1, sizeof(S1) - 1) ||
580 		    !strncmp(buf, S2, sizeof(S2) - 1)) {
581 			print = 1;
582 			continue;
583 		} else if (!strncmp(buf, D1, sizeof(D1) - 1) ||
584 		    !strncmp(buf, D2, sizeof(D2) - 1))
585 			return;
586 		if (!print)
587 			continue;
588 		if (*buf == '\n')
589 			++lcnt;
590 		else {
591 			for(; lcnt; --lcnt)
592 				(void)putchar('\n');
593 			for (p = buf; isspace(*p); ++p);
594 			(void)fputs(p, stdout);
595 		}
596 	}
597 	(void)fclose(fp);
598 }
599 
600 /*
601  * cat --
602  *	cat out the file
603  */
604 static void
605 cat(fname)
606 	char *fname;
607 {
608 	int fd, n;
609 	char buf[2048];
610 
611 	if ((fd = open(fname, O_RDONLY, 0)) < 0) {
612 		warn("%s", fname);
613 		(void)cleanup();
614 		exit(1);
615 	}
616 	while ((n = read(fd, buf, sizeof(buf))) > 0)
617 		if (write(STDOUT_FILENO, buf, n) != n) {
618 			warn("write");
619 			(void)cleanup();
620 			exit (1);
621 		}
622 	if (n == -1) {
623 		warn("read");
624 		(void)cleanup();
625 		exit(1);
626 	}
627 	(void)close(fd);
628 }
629 
630 /*
631  * check_pager --
632  *	check the user supplied page information
633  */
634 static char *
635 check_pager(name)
636 	char *name;
637 {
638 	char *p, *save;
639 
640 	/*
641 	 * if the user uses "more", we make it "more -s"; watch out for
642 	 * PAGER = "mypager /usr/ucb/more"
643 	 */
644 	for (p = name; *p && !isspace(*p); ++p);
645 	for (; p > name && *p != '/'; --p);
646 	if (p != name)
647 		++p;
648 
649 	/* make sure it's "more", not "morex" */
650 	if (!strncmp(p, "more", 4) && (!p[4] || isspace(p[4]))){
651 		save = name;
652 		/* allocate space to add the "-s" */
653 		if (!(name =
654 		    malloc((u_int)(strlen(save) + sizeof("-s") + 1))))
655 			err(1, NULL);
656 		(void)sprintf(name, "%s %s", save, "-s");
657 	}
658 	return(name);
659 }
660 
661 /*
662  * jump --
663  *	strip out flag argument and jump
664  */
665 static void
666 jump(argv, flag, name)
667 	char **argv, *flag, *name;
668 {
669 	char **arg;
670 
671 	argv[0] = name;
672 	for (arg = argv + 1; *arg; ++arg)
673 		if (!strcmp(*arg, flag))
674 			break;
675 	for (; *arg; ++arg)
676 		arg[0] = arg[1];
677 	execvp(name, argv);
678 	(void)fprintf(stderr, "%s: Command not found.\n", name);
679 	exit(1);
680 }
681 
682 /*
683  * onsig --
684  *	If signaled, delete the temporary files.
685  */
686 static void
687 onsig(signo)
688 	int signo;
689 {
690 	(void)cleanup();
691 
692 	(void)signal(signo, SIG_DFL);
693 	(void)kill(getpid(), signo);
694 
695 	/* NOTREACHED */
696 	exit (1);
697 }
698 
699 /*
700  * cleanup --
701  *	Clean up temporary files, show any error messages.
702  */
703 static int
704 cleanup()
705 {
706 	TAG *intmpp, *missp;
707 	ENTRY *ep;
708 	int rval;
709 
710 	rval = 0;
711 	ep = (missp = getlist("_missing")) == NULL ?
712 	    NULL : missp->list.tqh_first;
713 	if (ep != NULL)
714 		for (; ep != NULL; ep = ep->q.tqe_next) {
715 			warnx("no entry for %s in the manual.", ep->s);
716 			rval = 1;
717 		}
718 
719 	ep = (intmpp = getlist("_intmp")) == NULL ?
720 	    NULL : intmpp->list.tqh_first;
721 	for (; ep != NULL; ep = ep->q.tqe_next)
722 		(void)unlink(ep->s);
723 	return (rval);
724 }
725 
726 /*
727  * usage --
728  *	print usage message and die
729  */
730 static void
731 usage()
732 {
733 	(void)fprintf(stderr,
734     "usage: man [-ac] [-C file] [-M path] [-m path] [section] title ...\n");
735 	exit(1);
736 }
737