xref: /netbsd-src/bin/ksh/c_sh.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: c_sh.c,v 1.10 2005/06/26 19:09:00 christos Exp $	*/
2 
3 /*
4  * built-in Bourne commands
5  */
6 #include <sys/cdefs.h>
7 
8 #ifndef lint
9 __RCSID("$NetBSD: c_sh.c,v 1.10 2005/06/26 19:09:00 christos Exp $");
10 #endif
11 
12 
13 #include "sh.h"
14 #include "ksh_stat.h" 	/* umask() */
15 #include "ksh_time.h"
16 #include "ksh_times.h"
17 
18 static	char *clocktos ARGS((clock_t t));
19 
20 
21 /* :, false and true */
22 int
23 c_label(wp)
24 	char **wp;
25 {
26 	return wp[0][0] == 'f' ? 1 : 0;
27 }
28 
29 int
30 c_shift(wp)
31 	char **wp;
32 {
33 	register struct block *l = e->loc;
34 	register int n;
35 	long val;
36 	char *arg;
37 
38 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
39 		return 1;
40 	arg = wp[builtin_opt.optind];
41 
42 	if (arg) {
43 		evaluate(arg, &val, KSH_UNWIND_ERROR);
44 		n = val;
45 	} else
46 		n = 1;
47 	if (n < 0) {
48 		bi_errorf("%s: bad number", arg);
49 		return (1);
50 	}
51 	if (l->argc < n) {
52 		bi_errorf("nothing to shift");
53 		return (1);
54 	}
55 	l->argv[n] = l->argv[0];
56 	l->argv += n;
57 	l->argc -= n;
58 	return 0;
59 }
60 
61 int
62 c_umask(wp)
63 	char **wp;
64 {
65 	register int i;
66 	register char *cp;
67 	int symbolic = 0;
68 	int old_umask;
69 	int optc;
70 
71 	while ((optc = ksh_getopt(wp, &builtin_opt, "S")) != EOF)
72 		switch (optc) {
73 		  case 'S':
74 			symbolic = 1;
75 			break;
76 		  case '?':
77 			return 1;
78 		}
79 	cp = wp[builtin_opt.optind];
80 	if (cp == NULL) {
81 		old_umask = umask(0);
82 		umask(old_umask);
83 		if (symbolic) {
84 			char buf[18];
85 			int j;
86 
87 			old_umask = ~old_umask;
88 			cp = buf;
89 			for (i = 0; i < 3; i++) {
90 				*cp++ = "ugo"[i];
91 				*cp++ = '=';
92 				for (j = 0; j < 3; j++)
93 					if (old_umask & (1 << (8 - (3*i + j))))
94 						*cp++ = "rwx"[j];
95 				*cp++ = ',';
96 			}
97 			cp[-1] = '\0';
98 			shprintf("%s\n", buf);
99 		} else
100 			shprintf("%#3.3o\n", old_umask);
101 	} else {
102 		int new_umask;
103 
104 		if (digit(*cp)) {
105 			for (new_umask = 0; *cp >= '0' && *cp <= '7'; cp++)
106 				new_umask = new_umask * 8 + (*cp - '0');
107 			if (*cp) {
108 				bi_errorf("bad number");
109 				return 1;
110 			}
111 		} else {
112 			/* symbolic format */
113 			int positions, new_val;
114 			char op;
115 
116 			old_umask = umask(0);
117 			umask(old_umask); /* in case of error */
118 			old_umask = ~old_umask;
119 			new_umask = old_umask;
120 			positions = 0;
121 			while (*cp) {
122 				while (*cp && strchr("augo", *cp))
123 					switch (*cp++) {
124 					case 'a': positions |= 0111; break;
125 					case 'u': positions |= 0100; break;
126 					case 'g': positions |= 0010; break;
127 					case 'o': positions |= 0001; break;
128 					}
129 				if (!positions)
130 					positions = 0111; /* default is a */
131 				if (!strchr("=+-", op = *cp))
132 					break;
133 				cp++;
134 				new_val = 0;
135 				while (*cp && strchr("rwxugoXs", *cp))
136 					switch (*cp++) {
137 					case 'r': new_val |= 04; break;
138 					case 'w': new_val |= 02; break;
139 					case 'x': new_val |= 01; break;
140 					case 'u': new_val |= old_umask >> 6;
141 						  break;
142 					case 'g': new_val |= old_umask >> 3;
143 						  break;
144 					case 'o': new_val |= old_umask >> 0;
145 						  break;
146 					case 'X': if (old_umask & 0111)
147 							new_val |= 01;
148 						  break;
149 					case 's': /* ignored */
150 						  break;
151 					}
152 				new_val = (new_val & 07) * positions;
153 				switch (op) {
154 				case '-':
155 					new_umask &= ~new_val;
156 					break;
157 				case '=':
158 					new_umask = new_val
159 					    | (new_umask & ~(positions * 07));
160 					break;
161 				case '+':
162 					new_umask |= new_val;
163 				}
164 				if (*cp == ',') {
165 					positions = 0;
166 					cp++;
167 				} else if (!strchr("=+-", *cp))
168 					break;
169 			}
170 			if (*cp) {
171 				bi_errorf("bad mask");
172 				return 1;
173 			}
174 			new_umask = ~new_umask;
175 		}
176 		umask(new_umask);
177 	}
178 	return 0;
179 }
180 
181 int
182 c_dot(wp)
183 	char **wp;
184 {
185 	char *file, *cp;
186 	char **argv;
187 	int argc;
188 	int i;
189 	int err;
190 
191 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
192 		return 1;
193 
194 	if ((cp = wp[builtin_opt.optind]) == NULL)
195 		return 0;
196 	file = search(cp, path, R_OK, &err);
197 	if (file == NULL) {
198 		bi_errorf("%s: %s", cp, err ? strerror(err) : "not found");
199 		return 1;
200 	}
201 
202 	/* Set positional parameters? */
203 	if (wp[builtin_opt.optind + 1]) {
204 		argv = wp + builtin_opt.optind;
205 		argv[0] = e->loc->argv[0]; /* preserve $0 */
206 		for (argc = 0; argv[argc + 1]; argc++)
207 			;
208 	} else {
209 		argc = 0;
210 		argv = (char **) 0;
211 	}
212 	i = include(file, argc, argv, 0);
213 	if (i < 0) { /* should not happen */
214 		bi_errorf("%s: %s", cp, strerror(errno));
215 		return 1;
216 	}
217 	return i;
218 }
219 
220 int
221 c_wait(wp)
222 	char **wp;
223 {
224 	int UNINITIALIZED(rv);
225 	int sig;
226 
227 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
228 		return 1;
229 	wp += builtin_opt.optind;
230 	if (*wp == (char *) 0) {
231 		while (waitfor((char *) 0, &sig) >= 0)
232 			;
233 		rv = sig;
234 	} else {
235 		for (; *wp; wp++)
236 			rv = waitfor(*wp, &sig);
237 		if (rv < 0)
238 			rv = sig ? sig : 127; /* magic exit code: bad job-id */
239 	}
240 	return rv;
241 }
242 
243 int
244 c_read(wp)
245 	char **wp;
246 {
247 	register int c = 0;
248 	int expandv = 1, history = 0;
249 	int expanding;
250 	int ecode = 0;
251 	register char *cp;
252 	int fd = 0;
253 	struct shf *shf;
254 	int optc;
255 	const char *emsg;
256 	XString cs, xs;
257 	struct tbl *vp;
258 	char UNINITIALIZED(*xp);
259 	static char REPLY[] = "REPLY";
260 
261 	while ((optc = ksh_getopt(wp, &builtin_opt, "prsu,")) != EOF)
262 		switch (optc) {
263 #ifdef KSH
264 		  case 'p':
265 			if ((fd = coproc_getfd(R_OK, &emsg)) < 0) {
266 				bi_errorf("-p: %s", emsg);
267 				return 1;
268 			}
269 			break;
270 #endif /* KSH */
271 		  case 'r':
272 			expandv = 0;
273 			break;
274 		  case 's':
275 			history = 1;
276 			break;
277 		  case 'u':
278 			if (!*(cp = builtin_opt.optarg))
279 				fd = 0;
280 			else if ((fd = check_fd(cp, R_OK, &emsg)) < 0) {
281 				bi_errorf("-u: %s: %s", cp, emsg);
282 				return 1;
283 			}
284 			break;
285 		  case '?':
286 			return 1;
287 		}
288 	wp += builtin_opt.optind;
289 
290 	if (*wp == NULL)
291 		*--wp = REPLY;
292 
293 	/* Since we can't necessarily seek backwards on non-regular files,
294 	 * don't buffer them so we can't read too much.
295 	 */
296 	shf = shf_reopen(fd, SHF_RD | SHF_INTERRUPT | can_seek(fd), shl_spare);
297 
298 	if ((cp = strchr(*wp, '?')) != NULL) {
299 		*cp = 0;
300 		if (isatty(fd)) {
301 			/* at&t ksh says it prints prompt on fd if it's open
302 			 * for writing and is a tty, but it doesn't do it
303 			 * (it also doesn't check the interactive flag,
304 			 * as is indicated in the Kornshell book).
305 			 */
306 			shellf("%s", cp+1);
307 		}
308 	}
309 
310 #ifdef KSH
311 	/* If we are reading from the co-process for the first time,
312 	 * make sure the other side of the pipe is closed first.  This allows
313 	 * the detection of eof.
314 	 *
315 	 * This is not compatible with at&t ksh... the fd is kept so another
316 	 * coproc can be started with same output, however, this means eof
317 	 * can't be detected...  This is why it is closed here.
318 	 * If this call is removed, remove the eof check below, too.
319 	 * coproc_readw_close(fd);
320 	 */
321 #endif /* KSH */
322 
323 	if (history)
324 		Xinit(xs, xp, 128, ATEMP);
325 	expanding = 0;
326 	Xinit(cs, cp, 128, ATEMP);
327 	for (; *wp != NULL; wp++) {
328 		for (cp = Xstring(cs, cp); ; ) {
329 			if (c == '\n' || c == EOF)
330 				break;
331 			while (1) {
332 				c = shf_getc(shf);
333 				if (c == '\0'
334 #ifdef OS2
335 				    || c == '\r'
336 #endif /* OS2 */
337 				    )
338 					continue;
339 				if (c == EOF && shf_error(shf)
340 				    && shf_errno(shf) == EINTR)
341 				{
342 					/* Was the offending signal one that
343 					 * would normally kill a process?
344 					 * If so, pretend the read was killed.
345 					 */
346 					ecode = fatal_trap_check();
347 
348 					/* non fatal (eg, CHLD), carry on */
349 					if (!ecode) {
350 						shf_clearerr(shf);
351 						continue;
352 					}
353 				}
354 				break;
355 			}
356 			if (history) {
357 				Xcheck(xs, xp);
358 				Xput(xs, xp, c);
359 			}
360 			Xcheck(cs, cp);
361 			if (expanding) {
362 				expanding = 0;
363 				if (c == '\n') {
364 					c = 0;
365 					if (Flag(FTALKING_I) && isatty(fd)) {
366 						/* set prompt in case this is
367 						 * called from .profile or $ENV
368 						 */
369 						set_prompt(PS2, (Source *) 0);
370 						pprompt(prompt, 0);
371 					}
372 				} else if (c != EOF)
373 					Xput(cs, cp, c);
374 				continue;
375 			}
376 			if (expandv && c == '\\') {
377 				expanding = 1;
378 				continue;
379 			}
380 			if (c == '\n' || c == EOF)
381 				break;
382 			if (ctype(c, C_IFS)) {
383 				if (Xlength(cs, cp) == 0 && ctype(c, C_IFSWS))
384 					continue;
385 				if (wp[1])
386 					break;
387 			}
388 			Xput(cs, cp, c);
389 		}
390 		/* strip trailing IFS white space from last variable */
391 		if (!wp[1])
392 			while (Xlength(cs, cp) && ctype(cp[-1], C_IFS)
393 			       && ctype(cp[-1], C_IFSWS))
394 				cp--;
395 		Xput(cs, cp, '\0');
396 		vp = global(*wp);
397 		/* Must be done before setting export. */
398 		if (vp->flag & RDONLY) {
399 			shf_flush(shf);
400 			bi_errorf("%s is read only", *wp);
401 			return 1;
402 		}
403 		if (Flag(FEXPORT))
404 			typeset(*wp, EXPORT, 0, 0, 0);
405 		if (!setstr(vp, Xstring(cs, cp), KSH_RETURN_ERROR)) {
406 		    shf_flush(shf);
407 		    return 1;
408 		}
409 	}
410 
411 	shf_flush(shf);
412 	if (history) {
413 		Xput(xs, xp, '\0');
414 		source->line++;
415 		histsave(source->line, Xstring(xs, xp), 1);
416 		Xfree(xs, xp);
417 	}
418 #ifdef KSH
419 	/* if this is the co-process fd, close the file descriptor
420 	 * (can get eof if and only if all processes are have died, ie,
421 	 * coproc.njobs is 0 and the pipe is closed).
422 	 */
423 	if (c == EOF && !ecode)
424 		coproc_read_close(fd);
425 #endif /* KSH */
426 
427 	return ecode ? ecode : c == EOF;
428 }
429 
430 int
431 c_eval(wp)
432 	char **wp;
433 {
434 	register struct source *s;
435 
436 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
437 		return 1;
438 	s = pushs(SWORDS, ATEMP);
439 	s->u.strv = wp + builtin_opt.optind;
440 	if (!Flag(FPOSIX)) {
441 		/*
442 		 * Handle case where the command is empty due to failed
443 		 * command substitution, eg, eval "$(false)".
444 		 * In this case, shell() will not set/change exstat (because
445 		 * compiled tree is empty), so will use this value.
446 		 * subst_exstat is cleared in execute(), so should be 0 if
447 		 * there were no substitutions.
448 		 *
449 		 * A strict reading of POSIX says we don't do this (though
450 		 * it is traditionally done). [from 1003.2-1992]
451 		 *    3.9.1: Simple Commands
452 		 *	... If there is a command name, execution shall
453 		 *	continue as described in 3.9.1.1.  If there
454 		 *	is no command name, but the command contained a command
455 		 *	substitution, the command shall complete with the exit
456 		 *	status of the last command substitution
457 		 *    3.9.1.1: Command Search and Execution
458 		 *	...(1)...(a) If the command name matches the name of
459 		 *	a special built-in utility, that special built-in
460 		 *	utility shall be invoked.
461 		 * 3.14.5: Eval
462 		 *	... If there are no arguments, or only null arguments,
463 		 *	eval shall return an exit status of zero.
464 		 */
465 		exstat = subst_exstat;
466 	}
467 
468 	return shell(s, FALSE);
469 }
470 
471 int
472 c_trap(wp)
473 	char **wp;
474 {
475 	int i;
476 	char *s;
477 	register Trap *p;
478 
479 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
480 		return 1;
481 	wp += builtin_opt.optind;
482 
483 	if (*wp == NULL) {
484 		int anydfl = 0;
485 
486 		for (p = sigtraps, i = SIGNALS+1; --i >= 0; p++) {
487 			if (p->trap == NULL)
488 				anydfl = 1;
489 			else {
490 				shprintf("trap -- ");
491 				print_value_quoted(p->trap);
492 				shprintf(" %s\n", p->name);
493 			}
494 		}
495 #if 0 /* this is ugly and not clear POSIX needs it */
496 		/* POSIX may need this so output of trap can be saved and
497 		 * used to restore trap conditions
498 		 */
499 		if (anydfl) {
500 			shprintf("trap -- -");
501 			for (p = sigtraps, i = SIGNALS+1; --i >= 0; p++)
502 				if (p->trap == NULL && p->name)
503 					shprintf(" %s", p->name);
504 			shprintf(newline);
505 		}
506 #endif
507 		return 0;
508 	}
509 
510 	/*
511 	 * Use case sensitive lookup for first arg so the
512 	 * command 'exit' isn't confused with the pseudo-signal
513 	 * 'EXIT'.
514 	 */
515 	s = (gettrap(*wp, FALSE) == NULL) ? *wp++ : NULL; /* get command */
516 	if (s != NULL && s[0] == '-' && s[1] == '\0')
517 		s = NULL;
518 
519 	/* set/clear traps */
520 	while (*wp != NULL) {
521 		p = gettrap(*wp++, TRUE);
522 		if (p == NULL) {
523 			bi_errorf("bad signal %s", wp[-1]);
524 			return 1;
525 		}
526 		settrap(p, s);
527 	}
528 	return 0;
529 }
530 
531 int
532 c_exitreturn(wp)
533 	char **wp;
534 {
535 	int how = LEXIT;
536 	int n;
537 	char *arg;
538 
539 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
540 		return 1;
541 	arg = wp[builtin_opt.optind];
542 
543 	if (arg) {
544 	    if (!getn(arg, &n)) {
545 		    exstat = 1;
546 		    warningf(TRUE, "%s: bad number", arg);
547 	    } else
548 		    exstat = n;
549 	}
550 	if (wp[0][0] == 'r') { /* return */
551 		struct env *ep;
552 
553 		/* need to tell if this is exit or return so trap exit will
554 		 * work right (POSIX)
555 		 */
556 		for (ep = e; ep; ep = ep->oenv)
557 			if (STOP_RETURN(ep->type)) {
558 				how = LRETURN;
559 				break;
560 			}
561 	}
562 
563 	if (how == LEXIT && !really_exit && j_stopped_running()) {
564 		really_exit = 1;
565 		how = LSHELL;
566 	}
567 
568 	quitenv();	/* get rid of any i/o redirections */
569 	unwind(how);
570 	/*NOTREACHED*/
571 	return 0;
572 }
573 
574 int
575 c_brkcont(wp)
576 	char **wp;
577 {
578 	int n, quit;
579 	struct env *ep, *last_ep = (struct env *) 0;
580 	char *arg;
581 
582 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
583 		return 1;
584 	arg = wp[builtin_opt.optind];
585 
586 	if (!arg)
587 		n = 1;
588 	else if (!bi_getn(arg, &n))
589 		return 1;
590 	quit = n;
591 	if (quit <= 0) {
592 		/* at&t ksh does this for non-interactive shells only - weird */
593 		bi_errorf("%s: bad value", arg);
594 		return 1;
595 	}
596 
597 	/* Stop at E_NONE, E_PARSE, E_FUNC, or E_INCL */
598 	for (ep = e; ep && !STOP_BRKCONT(ep->type); ep = ep->oenv)
599 		if (ep->type == E_LOOP) {
600 			if (--quit == 0)
601 				break;
602 			ep->flags |= EF_BRKCONT_PASS;
603 			last_ep = ep;
604 		}
605 
606 	if (quit) {
607 		/* at&t ksh doesn't print a message - just does what it
608 		 * can.  We print a message 'cause it helps in debugging
609 		 * scripts, but don't generate an error (ie, keep going).
610 		 */
611 		if (n == quit) {
612 			warningf(TRUE, "%s: cannot %s", wp[0], wp[0]);
613 			return 0;
614 		}
615 		/* POSIX says if n is too big, the last enclosing loop
616 		 * shall be used.  Doesn't say to print an error but we
617 		 * do anyway 'cause the user messed up.
618 		 */
619 		last_ep->flags &= ~EF_BRKCONT_PASS;
620 		warningf(TRUE, "%s: can only %s %d level(s)",
621 			wp[0], wp[0], n - quit);
622 	}
623 
624 	unwind(*wp[0] == 'b' ? LBREAK : LCONTIN);
625 	/*NOTREACHED*/
626 }
627 
628 int
629 c_set(wp)
630 	char **wp;
631 {
632 	int argi, setargs;
633 	struct block *l = e->loc;
634 	register char **owp = wp;
635 
636 	if (wp[1] == NULL) {
637 		static const char *const args [] = { "set", "-", NULL };
638 		return c_typeset((char **)__UNCONST(args));
639 	}
640 
641 	argi = parse_args(wp, OF_SET, &setargs);
642 	if (argi < 0)
643 		return 1;
644 	/* set $# and $* */
645 	if (setargs) {
646 		owp = wp += argi - 1;
647 		wp[0] = l->argv[0]; /* save $0 */
648 		while (*++wp != NULL)
649 			*wp = str_save(*wp, &l->area);
650 		l->argc = wp - owp - 1;
651 		l->argv = (char **) alloc(sizeofN(char *, l->argc+2), &l->area);
652 		for (wp = l->argv; (*wp++ = *owp++) != NULL; )
653 			;
654 	}
655 	/* POSIX says set exit status is 0, but old scripts that use
656 	 * getopt(1), use the construct: set -- `getopt ab:c "$@"`
657 	 * which assumes the exit value set will be that of the ``
658 	 * (subst_exstat is cleared in execute() so that it will be 0
659 	 * if there are no command substitutions).
660 	 */
661 	return Flag(FPOSIX) ? 0 : subst_exstat;
662 }
663 
664 int
665 c_unset(wp)
666 	char **wp;
667 {
668 	register char *id;
669 	int optc, unset_var = 1;
670 	int ret = 0;
671 
672 	while ((optc = ksh_getopt(wp, &builtin_opt, "fv")) != EOF)
673 		switch (optc) {
674 		  case 'f':
675 			unset_var = 0;
676 			break;
677 		  case 'v':
678 			unset_var = 1;
679 			break;
680 		  case '?':
681 			return 1;
682 		}
683 	wp += builtin_opt.optind;
684 	for (; (id = *wp) != NULL; wp++)
685 		if (unset_var) {	/* unset variable */
686 			struct tbl *vp = global(id);
687 
688 			if (!(vp->flag & ISSET))
689 			    ret = 1;
690 			if ((vp->flag&RDONLY)) {
691 				bi_errorf("%s is read only", vp->name);
692 				return 1;
693 			}
694 			unset(vp, strchr(id, '[') ? 1 : 0);
695 		} else {		/* unset function */
696 			if (define(id, (struct op *) NULL))
697 				ret = 1;
698 		}
699 	return ret;
700 }
701 
702 int
703 c_times(wp)
704 	char **wp;
705 {
706 	struct tms all;
707 
708 	(void) ksh_times(&all);
709 	shprintf("Shell: %8ss user ", clocktos(all.tms_utime));
710 	shprintf("%8ss system\n", clocktos(all.tms_stime));
711 	shprintf("Kids:  %8ss user ", clocktos(all.tms_cutime));
712 	shprintf("%8ss system\n", clocktos(all.tms_cstime));
713 
714 	return 0;
715 }
716 
717 /*
718  * time pipeline (really a statement, not a built-in command)
719  */
720 int
721 timex(t, f)
722 	struct op *t;
723 	int f;
724 {
725 #define TF_NOARGS	BIT(0)
726 #define TF_NOREAL	BIT(1)		/* don't report real time */
727 #define TF_POSIX	BIT(2)		/* report in posix format */
728 	int rv = 0;
729 	struct tms t0, t1, tms;
730 	clock_t t0t, t1t = 0;
731 	int tf = 0;
732 	extern clock_t j_usrtime, j_systime; /* computed by j_wait */
733 	char opts[1];
734 
735 	t0t = ksh_times(&t0);
736 	if (t->left) {
737 		/*
738 		 * Two ways of getting cpu usage of a command: just use t0
739 		 * and t1 (which will get cpu usage from other jobs that
740 		 * finish while we are executing t->left), or get the
741 		 * cpu usage of t->left. at&t ksh does the former, while
742 		 * pdksh tries to do the later (the j_usrtime hack doesn't
743 		 * really work as it only counts the last job).
744 		 */
745 		j_usrtime = j_systime = 0;
746 		if (t->left->type == TCOM)
747 			t->left->str = opts;
748 		opts[0] = 0;
749 		rv = execute(t->left, f | XTIME);
750 		tf |= opts[0];
751 		t1t = ksh_times(&t1);
752 	} else
753 		tf = TF_NOARGS;
754 
755 	if (tf & TF_NOARGS) { /* ksh93 - report shell times (shell+kids) */
756 		tf |= TF_NOREAL;
757 		tms.tms_utime = t0.tms_utime + t0.tms_cutime;
758 		tms.tms_stime = t0.tms_stime + t0.tms_cstime;
759 	} else {
760 		tms.tms_utime = t1.tms_utime - t0.tms_utime + j_usrtime;
761 		tms.tms_stime = t1.tms_stime - t0.tms_stime + j_systime;
762 	}
763 
764 	if (!(tf & TF_NOREAL))
765 		shf_fprintf(shl_out,
766 			tf & TF_POSIX ? "real %8s\n" : "%8ss real ",
767 			clocktos(t1t - t0t));
768 	shf_fprintf(shl_out, tf & TF_POSIX ? "user %8s\n" : "%8ss user ",
769 		clocktos(tms.tms_utime));
770 	shf_fprintf(shl_out, tf & TF_POSIX ? "sys  %8s\n" : "%8ss system\n",
771 		clocktos(tms.tms_stime));
772 	shf_flush(shl_out);
773 
774 	return rv;
775 }
776 
777 void
778 timex_hook(t, app)
779 	struct op *t;
780 	char ** volatile *app;
781 {
782 	char **wp = *app;
783 	int optc;
784 	int i, j;
785 	Getopt opt;
786 
787 	ksh_getopt_reset(&opt, 0);
788 	opt.optind = 0;	/* start at the start */
789 	while ((optc = ksh_getopt(wp, &opt, ":p")) != EOF)
790 		switch (optc) {
791 		  case 'p':
792 			t->str[0] |= TF_POSIX;
793 			break;
794 		  case '?':
795 			errorf("time: -%s unknown option", opt.optarg);
796 		  case ':':
797 			errorf("time: -%s requires an argument",
798 				opt.optarg);
799 		}
800 	/* Copy command words down over options. */
801 	if (opt.optind != 0) {
802 		for (i = 0; i < opt.optind; i++)
803 			afree(wp[i], ATEMP);
804 		for (i = 0, j = opt.optind; (wp[i] = wp[j]); i++, j++)
805 			;
806 	}
807 	if (!wp[0])
808 		t->str[0] |= TF_NOARGS;
809 	*app = wp;
810 }
811 
812 static char *
813 clocktos(t)
814 	clock_t t;
815 {
816 	static char temp[22]; /* enough for 64 bit clock_t */
817 	register int i;
818 	register char *cp = temp + sizeof(temp);
819 
820 	/* note: posix says must use max precision, ie, if clk_tck is
821 	 * 1000, must print 3 places after decimal (if non-zero, else 1).
822 	 */
823 	if (CLK_TCK != 100)	/* convert to 1/100'ths */
824 	    t = (t < 1000000000/CLK_TCK) ?
825 		    (t * 100) / CLK_TCK : (t / CLK_TCK) * 100;
826 
827 	*--cp = '\0';
828 	for (i = -2; i <= 0 || t > 0; i++) {
829 		if (i == 0)
830 			*--cp = '.';
831 		*--cp = '0' + (char)(t%10);
832 		t /= 10;
833 	}
834 	return cp;
835 }
836 
837 /* exec with no args - args case is taken care of in comexec() */
838 int
839 c_exec(wp)
840 	char ** wp;
841 {
842 	int i;
843 
844 	/* make sure redirects stay in place */
845 	if (e->savefd != NULL) {
846 		for (i = 0; i < NUFILE; i++) {
847 			if (e->savefd[i] > 0)
848 				close(e->savefd[i]);
849 			/*
850 			 * For ksh keep anything > 2 private,
851 			 * for sh, let them be (POSIX says what
852 			 * happens is unspecified and the bourne shell
853 			 * keeps them open).
854 			 */
855 #ifdef KSH
856 			if (i > 2 && e->savefd[i])
857 				fd_clexec(i);
858 #endif /* KSH */
859 		}
860 		e->savefd = NULL;
861 	}
862 	return 0;
863 }
864 
865 /* dummy function, special case in comexec() */
866 int
867 c_builtin(wp)
868 	char ** wp;
869 {
870 	return 0;
871 }
872 
873 extern	int c_test ARGS((char **wp));		/* in c_test.c */
874 extern	int c_ulimit ARGS((char **wp));		/* in c_ulimit.c */
875 
876 /* A leading = means assignments before command are kept;
877  * a leading * means a POSIX special builtin;
878  * a leading + means a POSIX regular builtin
879  * (* and + should not be combined).
880  */
881 const struct builtin shbuiltins [] = {
882 	{"*=.", c_dot},
883 	{"*=:", c_label},
884 	{"[", c_test},
885 	{"*=break", c_brkcont},
886 	{"=builtin", c_builtin},
887 	{"*=continue", c_brkcont},
888 	{"*=eval", c_eval},
889 	{"*=exec", c_exec},
890 	{"*=exit", c_exitreturn},
891 	{"+false", c_label},
892 	{"*=return", c_exitreturn},
893 	{"*=set", c_set},
894 	{"*=shift", c_shift},
895 	{"=times", c_times},
896 	{"*=trap", c_trap},
897 	{"+=wait", c_wait},
898 	{"+read", c_read},
899 	{"test", c_test},
900 	{"+true", c_label},
901 	{"ulimit", c_ulimit},
902 	{"+umask", c_umask},
903 	{"*=unset", c_unset},
904 #ifdef OS2
905 	/* In OS2, the first line of a file can be "extproc name", which
906 	 * tells the command interpreter (cmd.exe) to use name to execute
907 	 * the file.  For this to be useful, ksh must ignore commands
908 	 * starting with extproc and this does the trick...
909 	 */
910 	{"extproc", c_label},
911 #endif /* OS2 */
912 	{NULL, NULL}
913 };
914