xref: /netbsd-src/bin/ksh/c_sh.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: c_sh.c,v 1.4 2001/02/04 19:26:04 christos Exp $	*/
2 
3 /*
4  * built-in Bourne commands
5  */
6 
7 #include "sh.h"
8 #include "ksh_stat.h" 	/* umask() */
9 #include "ksh_time.h"
10 #include "ksh_times.h"
11 
12 static	char *clocktos ARGS((clock_t t));
13 extern clock_t j_usrtime, j_systime; /* computed by j_wait */
14 
15 
16 /* :, false and true */
17 int
18 c_label(wp)
19 	char **wp;
20 {
21 	return wp[0][0] == 'f' ? 1 : 0;
22 }
23 
24 int
25 c_shift(wp)
26 	char **wp;
27 {
28 	register struct block *l = e->loc;
29 	register int n;
30 	long val;
31 	char *arg;
32 
33 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
34 		return 1;
35 	arg = wp[builtin_opt.optind];
36 
37 	if (arg) {
38 		evaluate(arg, &val, KSH_UNWIND_ERROR);
39 		n = val;
40 	} else
41 		n = 1;
42 	if (n < 0) {
43 		bi_errorf("%s: bad number", arg);
44 		return (1);
45 	}
46 	if (l->argc < n) {
47 		bi_errorf("nothing to shift");
48 		return (1);
49 	}
50 	l->argv[n] = l->argv[0];
51 	l->argv += n;
52 	l->argc -= n;
53 	return 0;
54 }
55 
56 int
57 c_umask(wp)
58 	char **wp;
59 {
60 	register int i;
61 	register char *cp;
62 	int symbolic = 0;
63 	int old_umask;
64 	int optc;
65 
66 	while ((optc = ksh_getopt(wp, &builtin_opt, "S")) != EOF)
67 		switch (optc) {
68 		  case 'S':
69 			symbolic = 1;
70 			break;
71 		  case '?':
72 			return 1;
73 		}
74 	cp = wp[builtin_opt.optind];
75 	if (cp == NULL) {
76 		old_umask = umask(0);
77 		umask(old_umask);
78 		if (symbolic) {
79 			char buf[18];
80 			int j;
81 
82 			old_umask = ~old_umask;
83 			cp = buf;
84 			for (i = 0; i < 3; i++) {
85 				*cp++ = "ugo"[i];
86 				*cp++ = '=';
87 				for (j = 0; j < 3; j++)
88 					if (old_umask & (1 << (8 - (3*i + j))))
89 						*cp++ = "rwx"[j];
90 				*cp++ = ',';
91 			}
92 			cp[-1] = '\0';
93 			shprintf("%s\n", buf);
94 		} else
95 			shprintf("%#3.3o\n", old_umask);
96 	} else {
97 		int new_umask;
98 
99 		if (digit(*cp)) {
100 			for (new_umask = 0; *cp >= '0' && *cp <= '7'; cp++)
101 				new_umask = new_umask * 8 + (*cp - '0');
102 			if (*cp) {
103 				bi_errorf("bad number");
104 				return 1;
105 			}
106 		} else {
107 			/* symbolic format */
108 			int positions, new_val;
109 			char op;
110 
111 			old_umask = umask(0);
112 			umask(old_umask); /* in case of error */
113 			old_umask = ~old_umask;
114 			new_umask = old_umask;
115 			positions = 0;
116 			while (*cp) {
117 				while (*cp && strchr("augo", *cp))
118 					switch (*cp++) {
119 					case 'a': positions |= 0111; break;
120 					case 'u': positions |= 0100; break;
121 					case 'g': positions |= 0010; break;
122 					case 'o': positions |= 0001; break;
123 					}
124 				if (!positions)
125 					positions = 0111; /* default is a */
126 				if (!strchr("=+-", op = *cp))
127 					break;
128 				cp++;
129 				new_val = 0;
130 				while (*cp && strchr("rwxugoXs", *cp))
131 					switch (*cp++) {
132 					case 'r': new_val |= 04; break;
133 					case 'w': new_val |= 02; break;
134 					case 'x': new_val |= 01; break;
135 					case 'u': new_val |= old_umask >> 6;
136 						  break;
137 					case 'g': new_val |= old_umask >> 3;
138 						  break;
139 					case 'o': new_val |= old_umask >> 0;
140 						  break;
141 					case 'X': if (old_umask & 0111)
142 							new_val |= 01;
143 						  break;
144 					case 's': /* ignored */
145 						  break;
146 					}
147 				new_val = (new_val & 07) * positions;
148 				switch (op) {
149 				case '-':
150 					new_umask &= ~new_val;
151 					break;
152 				case '=':
153 					new_umask = new_val
154 					    | (new_umask & ~(positions * 07));
155 					break;
156 				case '+':
157 					new_umask |= new_val;
158 				}
159 				if (*cp == ',') {
160 					positions = 0;
161 					cp++;
162 				} else if (!strchr("=+-", *cp))
163 					break;
164 			}
165 			if (*cp) {
166 				bi_errorf("bad mask");
167 				return 1;
168 			}
169 			new_umask = ~new_umask;
170 		}
171 		umask(new_umask);
172 	}
173 	return 0;
174 }
175 
176 int
177 c_dot(wp)
178 	char **wp;
179 {
180 	char *file, *cp;
181 	char **argv;
182 	int argc;
183 	int i;
184 	int err;
185 
186 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
187 		return 1;
188 
189 	if ((cp = wp[builtin_opt.optind]) == NULL)
190 		return 0;
191 	file = search(cp, path, R_OK, &err);
192 	if (file == NULL) {
193 		bi_errorf("%s: %s", cp, err ? strerror(err) : "not found");
194 		return 1;
195 	}
196 
197 	/* Set positional parameters? */
198 	if (wp[builtin_opt.optind + 1]) {
199 		argv = wp + builtin_opt.optind;
200 		argv[0] = e->loc->argv[0]; /* preserve $0 */
201 		for (argc = 0; argv[argc + 1]; argc++)
202 			;
203 	} else {
204 		argc = 0;
205 		argv = (char **) 0;
206 	}
207 	i = include(file, argc, argv, 0);
208 	if (i < 0) { /* should not happen */
209 		bi_errorf("%s: %s", cp, strerror(errno));
210 		return 1;
211 	}
212 	return i;
213 }
214 
215 int
216 c_wait(wp)
217 	char **wp;
218 {
219 	int UNINITIALIZED(rv);
220 	int sig;
221 
222 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
223 		return 1;
224 	wp += builtin_opt.optind;
225 	if (*wp == (char *) 0) {
226 		while (waitfor((char *) 0, &sig) >= 0)
227 			;
228 		rv = sig;
229 	} else {
230 		for (; *wp; wp++)
231 			rv = waitfor(*wp, &sig);
232 		if (rv < 0)
233 			rv = sig ? sig : 127; /* magic exit code: bad job-id */
234 	}
235 	return rv;
236 }
237 
238 int
239 c_read(wp)
240 	char **wp;
241 {
242 	register int c = 0;
243 	int expand = 1, history = 0;
244 	int expanding;
245 	int ecode = 0;
246 	register char *cp;
247 	int fd = 0;
248 	struct shf *shf;
249 	int optc;
250 	const char *emsg;
251 	XString cs, xs;
252 	struct tbl *vp;
253 	char UNINITIALIZED(*xp);
254 
255 	while ((optc = ksh_getopt(wp, &builtin_opt, "prsu,")) != EOF)
256 		switch (optc) {
257 #ifdef KSH
258 		  case 'p':
259 			if ((fd = coproc_getfd(R_OK, &emsg)) < 0) {
260 				bi_errorf("-p: %s", emsg);
261 				return 1;
262 			}
263 			break;
264 #endif /* KSH */
265 		  case 'r':
266 			expand = 0;
267 			break;
268 		  case 's':
269 			history = 1;
270 			break;
271 		  case 'u':
272 			if (!*(cp = builtin_opt.optarg))
273 				fd = 0;
274 			else if ((fd = check_fd(cp, R_OK, &emsg)) < 0) {
275 				bi_errorf("-u: %s: %s", cp, emsg);
276 				return 1;
277 			}
278 			break;
279 		  case '?':
280 			return 1;
281 		}
282 	wp += builtin_opt.optind;
283 
284 	if (*wp == NULL)
285 		*--wp = "REPLY";
286 
287 	/* Since we can't necessarily seek backwards on non-regular files,
288 	 * don't buffer them so we can't read too much.
289 	 */
290 	shf = shf_reopen(fd, SHF_RD | SHF_INTERRUPT | can_seek(fd), shl_spare);
291 
292 	if ((cp = strchr(*wp, '?')) != NULL) {
293 		*cp = 0;
294 		if (isatty(fd)) {
295 			/* at&t ksh says it prints prompt on fd if it's open
296 			 * for writing and is a tty, but it doesn't do it
297 			 * (it also doesn't check the interactive flag,
298 			 * as is indicated in the Kornshell book).
299 			 */
300 			shellf("%s", cp+1);
301 		}
302 	}
303 
304 #ifdef KSH
305 	/* If we are reading from the co-process for the first time,
306 	 * make sure the other side of the pipe is closed first.  This allows
307 	 * the detection of eof.
308 	 *
309 	 * This is not compatiable with at&t ksh... the fd is kept so another
310 	 * coproc can be started with same ouput, however, this means eof
311 	 * can't be detected...  This is why it is closed here.
312 	 * If this call is removed, remove the eof check below, too.
313 	* coproc_readw_close(fd);
314 	 */
315 #endif /* KSH */
316 
317 	if (history)
318 		Xinit(xs, xp, 128, ATEMP);
319 	expanding = 0;
320 	Xinit(cs, cp, 128, ATEMP);
321 	for (; *wp != NULL; wp++) {
322 		for (cp = Xstring(cs, cp); ; ) {
323 			if (c == '\n' || c == EOF)
324 				break;
325 			while (1) {
326 				c = shf_getc(shf);
327 				if (c == '\0'
328 #ifdef OS2
329 				    || c == '\r'
330 #endif /* OS2 */
331 				    )
332 					continue;
333 				if (c == EOF && shf_error(shf)
334 				    && shf_errno(shf) == EINTR)
335 				{
336 					/* Was the offending signal one that
337 					 * would normally kill a process?
338 					 * If so, pretend the read was killed.
339 					 */
340 					ecode = fatal_trap_check();
341 
342 					/* non fatal (eg, CHLD), carry on */
343 					if (!ecode) {
344 						shf_clearerr(shf);
345 						continue;
346 					}
347 				}
348 				break;
349 			}
350 			if (history) {
351 				Xcheck(xs, xp);
352 				Xput(xs, xp, c);
353 			}
354 			Xcheck(cs, cp);
355 			if (expanding) {
356 				expanding = 0;
357 				if (c == '\n') {
358 					c = 0;
359 					if (Flag(FTALKING_I) && isatty(fd)) {
360 						/* set prompt in case this is
361 						 * called from .profile or $ENV
362 						 */
363 						set_prompt(PS2, (Source *) 0);
364 						pprompt(prompt, 0);
365 					}
366 				} else if (c != EOF)
367 					Xput(cs, cp, c);
368 				continue;
369 			}
370 			if (expand && c == '\\') {
371 				expanding = 1;
372 				continue;
373 			}
374 			if (c == '\n' || c == EOF)
375 				break;
376 			if (ctype(c, C_IFS)) {
377 				if (Xlength(cs, cp) == 0 && ctype(c, C_IFSWS))
378 					continue;
379 				if (wp[1])
380 					break;
381 			}
382 			Xput(cs, cp, c);
383 		}
384 		/* strip trailing IFS white space from last variable */
385 		if (!wp[1])
386 			while (Xlength(cs, cp) && ctype(cp[-1], C_IFS)
387 			       && ctype(cp[-1], C_IFSWS))
388 				cp--;
389 		Xput(cs, cp, '\0');
390 		vp = global(*wp);
391 		/* Must be done before setting export. */
392 		if (vp->flag & RDONLY) {
393 			shf_flush(shf);
394 			bi_errorf("%s is read only", *wp);
395 			return 1;
396 		}
397 		if (Flag(FEXPORT))
398 			typeset(*wp, EXPORT, 0, 0, 0);
399 		if (!setstr(vp, Xstring(cs, cp), KSH_RETURN_ERROR)) {
400 		    shf_flush(shf);
401 		    return 1;
402 		}
403 	}
404 
405 	shf_flush(shf);
406 	if (history) {
407 		Xput(xs, xp, '\0');
408 		source->line++;
409 		histsave(source->line, Xstring(xs, xp), 1);
410 		Xfree(xs, xp);
411 	}
412 #ifdef KSH
413 	/* if this is the co-process fd, close the file descriptor
414 	 * (can get eof if and only if all processes are have died, ie,
415 	 * coproc.njobs is 0 and the pipe is closed).
416 	 */
417 	if (c == EOF && !ecode)
418 		coproc_read_close(fd);
419 #endif /* KSH */
420 
421 	return ecode ? ecode : c == EOF;
422 }
423 
424 int
425 c_eval(wp)
426 	char **wp;
427 {
428 	register struct source *s;
429 
430 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
431 		return 1;
432 	s = pushs(SWORDS, ATEMP);
433 	s->u.strv = wp + builtin_opt.optind;
434 	if (!Flag(FPOSIX)) {
435 		/*
436 		 * Handle case where the command is empty due to failed
437 		 * command substitution, eg, eval "$(false)".
438 		 * In this case, shell() will not set/change exstat (because
439 		 * compiled tree is empty), so will use this value.
440 		 * subst_exstat is cleared in execute(), so should be 0 if
441 		 * there were no substitutions.
442 		 *
443 		 * A strict reading of POSIX says we don't do this (though
444 		 * it is traditionally done). [from 1003.2-1992]
445 		 *    3.9.1: Simple Commands
446 		 *	... If there is a command name, execution shall
447 		 *	continue as described in 3.9.1.1.  If there
448 		 *	is no command name, but the command contained a command
449 		 *	substitution, the command shall complete with the exit
450 		 *	status of the last command substitution
451 		 *    3.9.1.1: Command Search and Execution
452 		 *	...(1)...(a) If the command name matches the name of
453 		 *	a special built-in utility, that special built-in
454 		 *	utility shall be invoked.
455 		 * 3.14.5: Eval
456 		 *	... If there are no arguments, or only null arguments,
457 		 *	eval shall return an exit status of zero.
458 		 */
459 		exstat = subst_exstat;
460 	}
461 
462 	return shell(s, FALSE);
463 }
464 
465 int
466 c_trap(wp)
467 	char **wp;
468 {
469 	int i;
470 	char *s;
471 	register Trap *p;
472 
473 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
474 		return 1;
475 	wp += builtin_opt.optind;
476 
477 	if (*wp == NULL) {
478 		int anydfl = 0;
479 
480 		for (p = sigtraps, i = SIGNALS+1; --i >= 0; p++) {
481 			if (p->trap == NULL)
482 				anydfl = 1;
483 			else {
484 				shprintf("trap -- ");
485 				print_value_quoted(p->trap);
486 				shprintf(" %s\n", p->name);
487 			}
488 		}
489 #if 0 /* this is ugly and not clear POSIX needs it */
490 		/* POSIX may need this so output of trap can be saved and
491 		 * used to restore trap conditions
492 		 */
493 		if (anydfl) {
494 			shprintf("trap -- -");
495 			for (p = sigtraps, i = SIGNALS+1; --i >= 0; p++)
496 				if (p->trap == NULL && p->name)
497 					shprintf(" %s", p->name);
498 			shprintf(newline);
499 		}
500 #endif
501 		return 0;
502 	}
503 
504 	/*
505 	 * Use case sensitive lookup for first arg so the
506 	 * command 'exit' isn't confused with the pseudo-signal
507 	 * 'EXIT'.
508 	 */
509 	s = (gettrap(*wp, FALSE) == NULL) ? *wp++ : NULL; /* get command */
510 	if (s != NULL && s[0] == '-' && s[1] == '\0')
511 		s = NULL;
512 
513 	/* set/clear traps */
514 	while (*wp != NULL) {
515 		p = gettrap(*wp++, TRUE);
516 		if (p == NULL) {
517 			bi_errorf("bad signal %s", wp[-1]);
518 			return 1;
519 		}
520 		settrap(p, s);
521 	}
522 	return 0;
523 }
524 
525 int
526 c_exitreturn(wp)
527 	char **wp;
528 {
529 	int how = LEXIT;
530 	int n;
531 	char *arg;
532 
533 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
534 		return 1;
535 	arg = wp[builtin_opt.optind];
536 
537 	if (arg) {
538 	    if (!getn(arg, &n)) {
539 		    exstat = 1;
540 		    warningf(TRUE, "%s: bad number", arg);
541 	    } else
542 		    exstat = n;
543 	}
544 	if (wp[0][0] == 'r') { /* return */
545 		struct env *ep;
546 
547 		/* need to tell if this is exit or return so trap exit will
548 		 * work right (POSIX)
549 		 */
550 		for (ep = e; ep; ep = ep->oenv)
551 			if (STOP_RETURN(ep->type)) {
552 				how = LRETURN;
553 				break;
554 			}
555 	}
556 
557 	if (how == LEXIT && !really_exit && j_stopped_running()) {
558 		really_exit = 1;
559 		how = LSHELL;
560 	}
561 
562 	quitenv();	/* get rid of any i/o redirections */
563 	unwind(how);
564 	/*NOTREACHED*/
565 	return 0;
566 }
567 
568 int
569 c_brkcont(wp)
570 	char **wp;
571 {
572 	int n, quit;
573 	struct env *ep, *last_ep = (struct env *) 0;
574 	char *arg;
575 
576 	if (ksh_getopt(wp, &builtin_opt, null) == '?')
577 		return 1;
578 	arg = wp[builtin_opt.optind];
579 
580 	if (!arg)
581 		n = 1;
582 	else if (!bi_getn(arg, &n))
583 		return 1;
584 	quit = n;
585 	if (quit <= 0) {
586 		/* at&t ksh does this for non-interactive shells only - weird */
587 		bi_errorf("%s: bad value", arg);
588 		return 1;
589 	}
590 
591 	/* Stop at E_NONE, E_PARSE, E_FUNC, or E_INCL */
592 	for (ep = e; ep && !STOP_BRKCONT(ep->type); ep = ep->oenv)
593 		if (ep->type == E_LOOP) {
594 			if (--quit == 0)
595 				break;
596 			ep->flags |= EF_BRKCONT_PASS;
597 			last_ep = ep;
598 		}
599 
600 	if (quit) {
601 		/* at&t ksh doesn't print a message - just does what it
602 		 * can.  We print a message 'cause it helps in debugging
603 		 * scripts, but don't generate an error (ie, keep going).
604 		 */
605 		if (n == quit) {
606 			warningf(TRUE, "%s: cannot %s", wp[0], wp[0]);
607 			return 0;
608 		}
609 		/* POSIX says if n is too big, the last enclosing loop
610 		 * shall be used.  Doesn't say to print an error but we
611 		 * do anyway 'cause the user messed up.
612 		 */
613 		last_ep->flags &= ~EF_BRKCONT_PASS;
614 		warningf(TRUE, "%s: can only %s %d level(s)",
615 			wp[0], wp[0], n - quit);
616 	}
617 
618 	unwind(*wp[0] == 'b' ? LBREAK : LCONTIN);
619 	/*NOTREACHED*/
620 }
621 
622 int
623 c_set(wp)
624 	char **wp;
625 {
626 	int argi, setargs;
627 	struct block *l = e->loc;
628 	register char **owp = wp;
629 
630 	if (wp[1] == NULL) {
631 		static const char *const args [] = { "set", "-", NULL };
632 		return c_typeset((char **) args);
633 	}
634 
635 	argi = parse_args(wp, OF_SET, &setargs);
636 	if (argi < 0)
637 		return 1;
638 	/* set $# and $* */
639 	if (setargs) {
640 		owp = wp += argi - 1;
641 		wp[0] = l->argv[0]; /* save $0 */
642 		while (*++wp != NULL)
643 			*wp = str_save(*wp, &l->area);
644 		l->argc = wp - owp - 1;
645 		l->argv = (char **) alloc(sizeofN(char *, l->argc+2), &l->area);
646 		for (wp = l->argv; (*wp++ = *owp++) != NULL; )
647 			;
648 	}
649 	/* POSIX says set exit status is 0, but old scripts that use
650 	 * getopt(1), use the construct: set -- `getopt ab:c "$@"`
651 	 * which assumes the exit value set will be that of the ``
652 	 * (subst_exstat is cleared in execute() so that it will be 0
653 	 * if there are no command substitutions).
654 	 */
655 	return Flag(FPOSIX) ? 0 : subst_exstat;
656 }
657 
658 int
659 c_unset(wp)
660 	char **wp;
661 {
662 	register char *id;
663 	int optc, unset_var = 1;
664 	int ret = 0;
665 
666 	while ((optc = ksh_getopt(wp, &builtin_opt, "fv")) != EOF)
667 		switch (optc) {
668 		  case 'f':
669 			unset_var = 0;
670 			break;
671 		  case 'v':
672 			unset_var = 1;
673 			break;
674 		  case '?':
675 			return 1;
676 		}
677 	wp += builtin_opt.optind;
678 	for (; (id = *wp) != NULL; wp++)
679 		if (unset_var) {	/* unset variable */
680 			struct tbl *vp = global(id);
681 
682 			if (!(vp->flag & ISSET))
683 			    ret = 1;
684 			if ((vp->flag&RDONLY)) {
685 				bi_errorf("%s is read only", vp->name);
686 				return 1;
687 			}
688 			unset(vp, strchr(id, '[') ? 1 : 0);
689 		} else {		/* unset function */
690 			if (define(id, (struct op *) NULL))
691 				ret = 1;
692 		}
693 	return ret;
694 }
695 
696 int
697 c_times(wp)
698 	char **wp;
699 {
700 	struct tms all;
701 
702 	(void) ksh_times(&all);
703 	shprintf("Shell: %8ss user ", clocktos(all.tms_utime));
704 	shprintf("%8ss system\n", clocktos(all.tms_stime));
705 	shprintf("Kids:  %8ss user ", clocktos(all.tms_cutime));
706 	shprintf("%8ss system\n", clocktos(all.tms_cstime));
707 
708 	return 0;
709 }
710 
711 /*
712  * time pipeline (really a statement, not a built-in command)
713  */
714 int
715 timex(t, f)
716 	struct op *t;
717 	int f;
718 {
719 #define TF_NOARGS	BIT(0)
720 #define TF_NOREAL	BIT(1)		/* don't report real time */
721 #define TF_POSIX	BIT(2)		/* report in posix format */
722 	int rv = 0;
723 	struct tms t0, t1, tms;
724 	clock_t t0t, t1t = 0;
725 	int tf = 0;
726 	char opts[1];
727 
728 	t0t = ksh_times(&t0);
729 	if (t->left) {
730 		/*
731 		 * Two ways of getting cpu usage of a command: just use t0
732 		 * and t1 (which will get cpu usage from other jobs that
733 		 * finish while we are executing t->left), or get the
734 		 * cpu usage of t->left. at&t ksh does the former, while
735 		 * pdksh tries to do the later (the j_usrtime hack doesn't
736 		 * really work as it only counts the last job).
737 		 */
738 		j_usrtime = j_systime = 0;
739 		if (t->left->type == TCOM)
740 			t->left->str = opts;
741 		opts[0] = 0;
742 		rv = execute(t->left, f | XTIME);
743 		tf |= opts[0];
744 		t1t = ksh_times(&t1);
745 	} else
746 		tf = TF_NOARGS;
747 
748 	if (tf & TF_NOARGS) { /* ksh93 - report shell times (shell+kids) */
749 		tf |= TF_NOREAL;
750 		tms.tms_utime = t0.tms_utime + t0.tms_cutime;
751 		tms.tms_stime = t0.tms_stime + t0.tms_cstime;
752 	} else {
753 		tms.tms_utime = t1.tms_utime - t0.tms_utime + j_usrtime;
754 		tms.tms_stime = t1.tms_stime - t0.tms_stime + j_systime;
755 	}
756 
757 	if (!(tf & TF_NOREAL))
758 		shf_fprintf(shl_out,
759 			tf & TF_POSIX ? "real %8s\n" : "%8ss real ",
760 			clocktos(t1t - t0t));
761 	shf_fprintf(shl_out, tf & TF_POSIX ? "user %8s\n" : "%8ss user ",
762 		clocktos(tms.tms_utime));
763 	shf_fprintf(shl_out, tf & TF_POSIX ? "sys  %8s\n" : "%8ss system\n",
764 		clocktos(tms.tms_stime));
765 	shf_flush(shl_out);
766 
767 	return rv;
768 }
769 
770 void
771 timex_hook(t, app)
772 	struct op *t;
773 	char ** volatile *app;
774 {
775 	char **wp = *app;
776 	int optc;
777 	int i, j;
778 	Getopt opt;
779 
780 	ksh_getopt_reset(&opt, 0);
781 	opt.optind = 0;	/* start at the start */
782 	while ((optc = ksh_getopt(wp, &opt, ":p")) != EOF)
783 		switch (optc) {
784 		  case 'p':
785 			t->str[0] |= TF_POSIX;
786 			break;
787 		  case '?':
788 			errorf("time: -%s unknown option", opt.optarg);
789 		  case ':':
790 			errorf("time: -%s requires an argument",
791 				opt.optarg);
792 		}
793 	/* Copy command words down over options. */
794 	if (opt.optind != 0) {
795 		for (i = 0; i < opt.optind; i++)
796 			afree(wp[i], ATEMP);
797 		for (i = 0, j = opt.optind; (wp[i] = wp[j]); i++, j++)
798 			;
799 	}
800 	if (!wp[0])
801 		t->str[0] |= TF_NOARGS;
802 	*app = wp;
803 }
804 
805 static char *
806 clocktos(t)
807 	clock_t t;
808 {
809 	static char temp[22]; /* enough for 64 bit clock_t */
810 	register int i;
811 	register char *cp = temp + sizeof(temp);
812 
813 	/* note: posix says must use max precision, ie, if clk_tck is
814 	 * 1000, must print 3 places after decimal (if non-zero, else 1).
815 	 */
816 	if (CLK_TCK != 100)	/* convert to 1/100'ths */
817 	    t = (t < 1000000000/CLK_TCK) ?
818 		    (t * 100) / CLK_TCK : (t / CLK_TCK) * 100;
819 
820 	*--cp = '\0';
821 	for (i = -2; i <= 0 || t > 0; i++) {
822 		if (i == 0)
823 			*--cp = '.';
824 		*--cp = '0' + (char)(t%10);
825 		t /= 10;
826 	}
827 	return cp;
828 }
829 
830 /* exec with no args - args case is taken care of in comexec() */
831 int
832 c_exec(wp)
833 	char ** wp;
834 {
835 	int i;
836 
837 	/* make sure redirects stay in place */
838 	if (e->savefd != NULL) {
839 		for (i = 0; i < NUFILE; i++) {
840 			if (e->savefd[i] > 0)
841 				close(e->savefd[i]);
842 			/*
843 			 * For ksh keep anything > 2 private,
844 			 * for sh, let them be (POSIX says what
845 			 * happens is unspecified and the bourne shell
846 			 * keeps them open).
847 			 */
848 #ifdef KSH
849 			if (i > 2 && e->savefd[i])
850 				fd_clexec(i);
851 #endif /* KSH */
852 		}
853 		e->savefd = NULL;
854 	}
855 	return 0;
856 }
857 
858 /* dummy function, special case in comexec() */
859 int
860 c_builtin(wp)
861 	char ** wp;
862 {
863 	return 0;
864 }
865 
866 /* A leading = means assignments before command are kept;
867  * a leading * means a POSIX special builtin;
868  * a leading + means a POSIX regular builtin
869  * (* and + should not be combined).
870  */
871 const struct builtin shbuiltins [] = {
872 	{"*=.", c_dot},
873 	{"*=:", c_label},
874 	{"[", c_test},
875 	{"*=break", c_brkcont},
876 	{"=builtin", c_builtin},
877 	{"*=continue", c_brkcont},
878 	{"*=eval", c_eval},
879 	{"*=exec", c_exec},
880 	{"*=exit", c_exitreturn},
881 	{"+false", c_label},
882 	{"*=return", c_exitreturn},
883 	{"*=set", c_set},
884 	{"*=shift", c_shift},
885 	{"=times", c_times},
886 	{"*=trap", c_trap},
887 	{"+=wait", c_wait},
888 	{"+read", c_read},
889 	{"test", c_test},
890 	{"+true", c_label},
891 	{"ulimit", c_ulimit},
892 	{"+umask", c_umask},
893 	{"*=unset", c_unset},
894 #ifdef OS2
895 	/* In OS2, the first line of a file can be "extproc name", which
896 	 * tells the command interpreter (cmd.exe) to use name to execute
897 	 * the file.  For this to be useful, ksh must ignore commands
898 	 * starting with extproc and this does the trick...
899 	 */
900 	{"extproc", c_label},
901 #endif /* OS2 */
902 	{NULL, NULL}
903 };
904