xref: /freebsd/contrib/less/command.c (revision 1c05a6ea6b849ff95e539c31adea887c644a6a01)
1 /* $FreeBSD$ */
2 /*
3  * Copyright (C) 1984-2017  Mark Nudelman
4  *
5  * You may distribute under the terms of either the GNU General Public
6  * License or the Less License, as specified in the README file.
7  *
8  * For more information, see the README file.
9  */
10 
11 
12 /*
13  * User-level command processor.
14  */
15 
16 #include "less.h"
17 #if MSDOS_COMPILER==WIN32C
18 #include <windows.h>
19 #endif
20 #include "position.h"
21 #include "option.h"
22 #include "cmd.h"
23 
24 extern int erase_char, erase2_char, kill_char;
25 extern int sigs;
26 extern int quit_if_one_screen;
27 extern int squished;
28 extern int sc_width;
29 extern int sc_height;
30 extern int swindow;
31 extern int jump_sline;
32 extern int quitting;
33 extern int wscroll;
34 extern int top_scroll;
35 extern int ignore_eoi;
36 extern int secure;
37 extern int hshift;
38 extern int bs_mode;
39 extern int show_attn;
40 extern int less_is_more;
41 extern POSITION highest_hilite;
42 extern char *every_first_cmd;
43 extern char *curr_altfilename;
44 extern char version[];
45 extern struct scrpos initial_scrpos;
46 extern IFILE curr_ifile;
47 extern void *ml_search;
48 extern void *ml_examine;
49 #if SHELL_ESCAPE || PIPEC
50 extern void *ml_shell;
51 #endif
52 #if EDITOR
53 extern char *editor;
54 extern char *editproto;
55 #endif
56 extern int screen_trashed;	/* The screen has been overwritten */
57 extern int shift_count;
58 extern int oldbot;
59 extern int forw_prompt;
60 extern int same_pos_bell;
61 
62 #if SHELL_ESCAPE
63 static char *shellcmd = NULL;	/* For holding last shell command for "!!" */
64 #endif
65 static int mca;			/* The multicharacter command (action) */
66 static int search_type;		/* The previous type of search */
67 static LINENUM number;		/* The number typed by the user */
68 static long fraction;		/* The fractional part of the number */
69 static struct loption *curropt;
70 static int opt_lower;
71 static int optflag;
72 static int optgetname;
73 static POSITION bottompos;
74 static int save_hshift;
75 static int save_bs_mode;
76 #if PIPEC
77 static char pipec;
78 #endif
79 
80 struct ungot {
81 	struct ungot *ug_next;
82 	char ug_char;
83 	char ug_end_command;
84 };
85 static struct ungot* ungot = NULL;
86 
87 static void multi_search();
88 
89 /*
90  * Move the cursor to start of prompt line before executing a command.
91  * This looks nicer if the command takes a long time before
92  * updating the screen.
93  */
94 	static void
95 cmd_exec()
96 {
97 #if HILITE_SEARCH
98 	clear_attn();
99 #endif
100 	clear_bot();
101 	flush();
102 }
103 
104 /*
105  * Set up the display to start a new multi-character command.
106  */
107 	static void
108 start_mca(action, prompt, mlist, cmdflags)
109 	int action;
110 	constant char *prompt;
111 	void *mlist;
112 	int cmdflags;
113 {
114 	mca = action;
115 	clear_bot();
116 	clear_cmd();
117 	cmd_putstr(prompt);
118 	set_mlist(mlist, cmdflags);
119 }
120 
121 	public int
122 in_mca()
123 {
124 	return (mca != 0 && mca != A_PREFIX);
125 }
126 
127 /*
128  * Set up the display to start a new search command.
129  */
130 	static void
131 mca_search()
132 {
133 #if HILITE_SEARCH
134 	if (search_type & SRCH_FILTER)
135 		mca = A_FILTER;
136 	else
137 #endif
138 	if (search_type & SRCH_FORW)
139 		mca = A_F_SEARCH;
140 	else
141 		mca = A_B_SEARCH;
142 
143 	clear_bot();
144 	clear_cmd();
145 
146 	if (search_type & SRCH_NO_MATCH)
147 		cmd_putstr("Non-match ");
148 	if (search_type & SRCH_FIRST_FILE)
149 		cmd_putstr("First-file ");
150 	if (search_type & SRCH_PAST_EOF)
151 		cmd_putstr("EOF-ignore ");
152 	if (search_type & SRCH_NO_MOVE)
153 		cmd_putstr("Keep-pos ");
154 	if (search_type & SRCH_NO_REGEX)
155 		cmd_putstr("Regex-off ");
156 
157 #if HILITE_SEARCH
158 	if (search_type & SRCH_FILTER)
159 		cmd_putstr("&/");
160 	else
161 #endif
162 	if (search_type & SRCH_FORW)
163 		cmd_putstr("/");
164 	else
165 		cmd_putstr("?");
166 	forw_prompt = 0;
167 	set_mlist(ml_search, 0);
168 }
169 
170 /*
171  * Set up the display to start a new toggle-option command.
172  */
173 	static void
174 mca_opt_toggle()
175 {
176 	int no_prompt;
177 	int flag;
178 	char *dash;
179 
180 	no_prompt = (optflag & OPT_NO_PROMPT);
181 	flag = (optflag & ~OPT_NO_PROMPT);
182 	dash = (flag == OPT_NO_TOGGLE) ? "_" : "-";
183 
184 	mca = A_OPT_TOGGLE;
185 	clear_bot();
186 	clear_cmd();
187 	cmd_putstr(dash);
188 	if (optgetname)
189 		cmd_putstr(dash);
190 	if (no_prompt)
191 		cmd_putstr("(P)");
192 	switch (flag)
193 	{
194 	case OPT_UNSET:
195 		cmd_putstr("+");
196 		break;
197 	case OPT_SET:
198 		cmd_putstr("!");
199 		break;
200 	}
201 	forw_prompt = 0;
202 	set_mlist(NULL, 0);
203 }
204 
205 /*
206  * Execute a multicharacter command.
207  */
208 	static void
209 exec_mca()
210 {
211 	char *cbuf;
212 
213 	cmd_exec();
214 	cbuf = get_cmdbuf();
215 
216 	switch (mca)
217 	{
218 	case A_F_SEARCH:
219 	case A_B_SEARCH:
220 		multi_search(cbuf, (int) number, 0);
221 		break;
222 #if HILITE_SEARCH
223 	case A_FILTER:
224 		search_type ^= SRCH_NO_MATCH;
225 		set_filter_pattern(cbuf, search_type);
226 		break;
227 #endif
228 	case A_FIRSTCMD:
229 		/*
230 		 * Skip leading spaces or + signs in the string.
231 		 */
232 		while (*cbuf == '+' || *cbuf == ' ')
233 			cbuf++;
234 		if (every_first_cmd != NULL)
235 			free(every_first_cmd);
236 		if (*cbuf == '\0')
237 			every_first_cmd = NULL;
238 		else
239 			every_first_cmd = save(cbuf);
240 		break;
241 	case A_OPT_TOGGLE:
242 		toggle_option(curropt, opt_lower, cbuf, optflag);
243 		curropt = NULL;
244 		break;
245 	case A_F_BRACKET:
246 		match_brac(cbuf[0], cbuf[1], 1, (int) number);
247 		break;
248 	case A_B_BRACKET:
249 		match_brac(cbuf[1], cbuf[0], 0, (int) number);
250 		break;
251 #if EXAMINE
252 	case A_EXAMINE:
253 		if (secure)
254 			break;
255 		edit_list(cbuf);
256 #if TAGS
257 		/* If tag structure is loaded then clean it up. */
258 		cleantags();
259 #endif
260 		break;
261 #endif
262 #if SHELL_ESCAPE
263 	case A_SHELL:
264 		/*
265 		 * !! just uses whatever is in shellcmd.
266 		 * Otherwise, copy cmdbuf to shellcmd,
267 		 * expanding any special characters ("%" or "#").
268 		 */
269 		if (*cbuf != '!')
270 		{
271 			if (shellcmd != NULL)
272 				free(shellcmd);
273 			shellcmd = fexpand(cbuf);
274 		}
275 
276 		if (secure)
277 			break;
278 		if (shellcmd == NULL)
279 			lsystem("", "!done");
280 		else
281 			lsystem(shellcmd, "!done");
282 		break;
283 #endif
284 #if PIPEC
285 	case A_PIPE:
286 		if (secure)
287 			break;
288 		(void) pipe_mark(pipec, cbuf);
289 		error("|done", NULL_PARG);
290 		break;
291 #endif
292 	}
293 }
294 
295 /*
296  * Is a character an erase or kill char?
297  */
298 	static int
299 is_erase_char(c)
300 	int c;
301 {
302 	return (c == erase_char || c == erase2_char || c == kill_char);
303 }
304 
305 /*
306  * Handle the first char of an option (after the initial dash).
307  */
308 	static int
309 mca_opt_first_char(c)
310     int c;
311 {
312 	int flag = (optflag & ~OPT_NO_PROMPT);
313 	if (flag == OPT_NO_TOGGLE)
314 	{
315 		switch (c)
316 		{
317 		case '_':
318 			/* "__" = long option name. */
319 			optgetname = TRUE;
320 			mca_opt_toggle();
321 			return (MCA_MORE);
322 		}
323 	} else
324 	{
325 		switch (c)
326 		{
327 		case '+':
328 			/* "-+" = UNSET. */
329 			optflag = (flag == OPT_UNSET) ?
330 				OPT_TOGGLE : OPT_UNSET;
331 			mca_opt_toggle();
332 			return (MCA_MORE);
333 		case '!':
334 			/* "-!" = SET */
335 			optflag = (flag == OPT_SET) ?
336 				OPT_TOGGLE : OPT_SET;
337 			mca_opt_toggle();
338 			return (MCA_MORE);
339 		case CONTROL('P'):
340 			optflag ^= OPT_NO_PROMPT;
341 			mca_opt_toggle();
342 			return (MCA_MORE);
343 		case '-':
344 			/* "--" = long option name. */
345 			optgetname = TRUE;
346 			mca_opt_toggle();
347 			return (MCA_MORE);
348 		}
349 	}
350 	/* Char was not handled here. */
351 	return (NO_MCA);
352 }
353 
354 /*
355  * Add a char to a long option name.
356  * See if we've got a match for an option name yet.
357  * If so, display the complete name and stop
358  * accepting chars until user hits RETURN.
359  */
360 	static int
361 mca_opt_nonfirst_char(c)
362 	int c;
363 {
364 	char *p;
365 	char *oname;
366 
367 	if (curropt != NULL)
368 	{
369 		/*
370 		 * Already have a match for the name.
371 		 * Don't accept anything but erase/kill.
372 		 */
373 		if (is_erase_char(c))
374 			return (MCA_DONE);
375 		return (MCA_MORE);
376 	}
377 	/*
378 	 * Add char to cmd buffer and try to match
379 	 * the option name.
380 	 */
381 	if (cmd_char(c) == CC_QUIT)
382 		return (MCA_DONE);
383 	p = get_cmdbuf();
384 	opt_lower = ASCII_IS_LOWER(p[0]);
385 	curropt = findopt_name(&p, &oname, NULL);
386 	if (curropt != NULL)
387 	{
388 		/*
389 		 * Got a match.
390 		 * Remember the option and
391 		 * display the full option name.
392 		 */
393 		cmd_reset();
394 		mca_opt_toggle();
395 		for (p = oname;  *p != '\0';  p++)
396 		{
397 			c = *p;
398 			if (!opt_lower && ASCII_IS_LOWER(c))
399 				c = ASCII_TO_UPPER(c);
400 			if (cmd_char(c) != CC_OK)
401 				return (MCA_DONE);
402 		}
403 	}
404 	return (MCA_MORE);
405 }
406 
407 /*
408  * Handle a char of an option toggle command.
409  */
410 	static int
411 mca_opt_char(c)
412 	int c;
413 {
414 	PARG parg;
415 
416 	/*
417 	 * This may be a short option (single char),
418 	 * or one char of a long option name,
419 	 * or one char of the option parameter.
420 	 */
421 	if (curropt == NULL && len_cmdbuf() == 0)
422 	{
423 		int ret = mca_opt_first_char(c);
424 		if (ret != NO_MCA)
425 			return (ret);
426 	}
427 	if (optgetname)
428 	{
429 		/* We're getting a long option name.  */
430 		if (c != '\n' && c != '\r')
431 			return (mca_opt_nonfirst_char(c));
432 		if (curropt == NULL)
433 		{
434 			parg.p_string = get_cmdbuf();
435 			error("There is no --%s option", &parg);
436 			return (MCA_DONE);
437 		}
438 		optgetname = FALSE;
439 		cmd_reset();
440 	} else
441 	{
442 		if (is_erase_char(c))
443 			return (NO_MCA);
444 		if (curropt != NULL)
445 			/* We're getting the option parameter. */
446 			return (NO_MCA);
447 		curropt = findopt(c);
448 		if (curropt == NULL)
449 		{
450 			parg.p_string = propt(c);
451 			error("There is no %s option", &parg);
452 			return (MCA_DONE);
453 		}
454 	}
455 	/*
456 	 * If the option which was entered does not take a
457 	 * parameter, toggle the option immediately,
458 	 * so user doesn't have to hit RETURN.
459 	 */
460 	if ((optflag & ~OPT_NO_PROMPT) != OPT_TOGGLE ||
461 	    !opt_has_param(curropt))
462 	{
463 		toggle_option(curropt, ASCII_IS_LOWER(c), "", optflag);
464 		return (MCA_DONE);
465 	}
466 	/*
467 	 * Display a prompt appropriate for the option parameter.
468 	 */
469 	start_mca(A_OPT_TOGGLE, opt_prompt(curropt), (void*)NULL, 0);
470 	return (MCA_MORE);
471 }
472 
473 /*
474  * Handle a char of a search command.
475  */
476 	static int
477 mca_search_char(c)
478 	int c;
479 {
480 	int flag = 0;
481 
482 	/*
483 	 * Certain characters as the first char of
484 	 * the pattern have special meaning:
485 	 *	!  Toggle the NO_MATCH flag
486 	 *	*  Toggle the PAST_EOF flag
487 	 *	@  Toggle the FIRST_FILE flag
488 	 */
489 	if (len_cmdbuf() > 0)
490 		return (NO_MCA);
491 
492 	switch (c)
493 	{
494 	case '*':
495 		if (less_is_more)
496 			break;
497 	case CONTROL('E'): /* ignore END of file */
498 		if (mca != A_FILTER)
499 			flag = SRCH_PAST_EOF;
500 		break;
501 	case '@':
502 		if (less_is_more)
503 			break;
504 	case CONTROL('F'): /* FIRST file */
505 		if (mca != A_FILTER)
506 			flag = SRCH_FIRST_FILE;
507 		break;
508 	case CONTROL('K'): /* KEEP position */
509 		if (mca != A_FILTER)
510 			flag = SRCH_NO_MOVE;
511 		break;
512 	case CONTROL('R'): /* Don't use REGULAR EXPRESSIONS */
513 		flag = SRCH_NO_REGEX;
514 		break;
515 	case CONTROL('N'): /* NOT match */
516 	case '!':
517 		flag = SRCH_NO_MATCH;
518 		break;
519 	}
520 
521 	if (flag != 0)
522 	{
523 		search_type ^= flag;
524 		mca_search();
525 		return (MCA_MORE);
526 	}
527 	return (NO_MCA);
528 }
529 
530 /*
531  * Handle a character of a multi-character command.
532  */
533 	static int
534 mca_char(c)
535 	int c;
536 {
537 	int ret;
538 
539 	switch (mca)
540 	{
541 	case 0:
542 		/*
543 		 * We're not in a multicharacter command.
544 		 */
545 		return (NO_MCA);
546 
547 	case A_PREFIX:
548 		/*
549 		 * In the prefix of a command.
550 		 * This not considered a multichar command
551 		 * (even tho it uses cmdbuf, etc.).
552 		 * It is handled in the commands() switch.
553 		 */
554 		return (NO_MCA);
555 
556 	case A_DIGIT:
557 		/*
558 		 * Entering digits of a number.
559 		 * Terminated by a non-digit.
560 		 */
561 		if (!((c >= '0' && c <= '9') || c == '.') &&
562 		  editchar(c, EC_PEEK|EC_NOHISTORY|EC_NOCOMPLETE|EC_NORIGHTLEFT) == A_INVALID)
563 		{
564 			/*
565 			 * Not part of the number.
566 			 * End the number and treat this char
567 			 * as a normal command character.
568 			 */
569 			number = cmd_int(&fraction);
570 			mca = 0;
571 			cmd_accept();
572 			return (NO_MCA);
573 		}
574 		break;
575 
576 	case A_OPT_TOGGLE:
577 		ret = mca_opt_char(c);
578 		if (ret != NO_MCA)
579 			return (ret);
580 		break;
581 
582 	case A_F_SEARCH:
583 	case A_B_SEARCH:
584 	case A_FILTER:
585 		ret = mca_search_char(c);
586 		if (ret != NO_MCA)
587 			return (ret);
588 		break;
589 
590 	default:
591 		/* Other multicharacter command. */
592 		break;
593 	}
594 
595 	/*
596 	 * The multichar command is terminated by a newline.
597 	 */
598 	if (c == '\n' || c == '\r')
599 	{
600 		/*
601 		 * Execute the command.
602 		 */
603 		exec_mca();
604 		return (MCA_DONE);
605 	}
606 
607 	/*
608 	 * Append the char to the command buffer.
609 	 */
610 	if (cmd_char(c) == CC_QUIT)
611 		/*
612 		 * Abort the multi-char command.
613 		 */
614 		return (MCA_DONE);
615 
616 	if ((mca == A_F_BRACKET || mca == A_B_BRACKET) && len_cmdbuf() >= 2)
617 	{
618 		/*
619 		 * Special case for the bracket-matching commands.
620 		 * Execute the command after getting exactly two
621 		 * characters from the user.
622 		 */
623 		exec_mca();
624 		return (MCA_DONE);
625 	}
626 
627 	/*
628 	 * Need another character.
629 	 */
630 	return (MCA_MORE);
631 }
632 
633 /*
634  * Discard any buffered file data.
635  */
636 	static void
637 clear_buffers()
638 {
639 	if (!(ch_getflags() & CH_CANSEEK))
640 		return;
641 	ch_flush();
642 	clr_linenum();
643 #if HILITE_SEARCH
644 	clr_hilite();
645 #endif
646 }
647 
648 /*
649  * Make sure the screen is displayed.
650  */
651 	static void
652 make_display()
653 {
654 	/*
655 	 * If nothing is displayed yet, display starting from initial_scrpos.
656 	 */
657 	if (empty_screen())
658 	{
659 		if (initial_scrpos.pos == NULL_POSITION)
660 			/*
661 			 * {{ Maybe this should be:
662 			 *    jump_loc(ch_zero(), jump_sline);
663 			 *    but this behavior seems rather unexpected
664 			 *    on the first screen. }}
665 			 */
666 			jump_loc(ch_zero(), 1);
667 		else
668 			jump_loc(initial_scrpos.pos, initial_scrpos.ln);
669 	} else if (screen_trashed)
670 	{
671 		int save_top_scroll = top_scroll;
672 		int save_ignore_eoi = ignore_eoi;
673 		top_scroll = 1;
674 		ignore_eoi = 0;
675 		if (screen_trashed == 2)
676 		{
677 			/* Special case used by ignore_eoi: re-open the input file
678 			 * and jump to the end of the file. */
679 			reopen_curr_ifile();
680 			jump_forw();
681 		}
682 		repaint();
683 		top_scroll = save_top_scroll;
684 		ignore_eoi = save_ignore_eoi;
685 	}
686 }
687 
688 /*
689  * Display the appropriate prompt.
690  */
691 	static void
692 prompt()
693 {
694 	constant char *p;
695 
696 	if (ungot != NULL && !ungot->ug_end_command)
697 	{
698 		/*
699 		 * No prompt necessary if commands are from
700 		 * ungotten chars rather than from the user.
701 		 */
702 		return;
703 	}
704 
705 	/*
706 	 * Make sure the screen is displayed.
707 	 */
708 	make_display();
709 	bottompos = position(BOTTOM_PLUS_ONE);
710 
711 	/*
712 	 * If we've hit EOF on the last file and the -E flag is set, quit.
713 	 */
714 	if (get_quit_at_eof() == OPT_ONPLUS &&
715 	    eof_displayed() && !(ch_getflags() & CH_HELPFILE) &&
716 	    next_ifile(curr_ifile) == NULL_IFILE)
717 		quit(QUIT_OK);
718 
719 	/*
720 	 * If the entire file is displayed and the -F flag is set, quit.
721 	 */
722 	if (quit_if_one_screen &&
723 	    entire_file_displayed() && !(ch_getflags() & CH_HELPFILE) &&
724 	    next_ifile(curr_ifile) == NULL_IFILE)
725 		quit(QUIT_OK);
726 
727 #if MSDOS_COMPILER==WIN32C
728 	/*
729 	 * In Win32, display the file name in the window title.
730 	 */
731 	if (!(ch_getflags() & CH_HELPFILE))
732 		SetConsoleTitle(pr_expand("Less?f - %f.", 0));
733 #endif
734 	/*
735 	 * Select the proper prompt and display it.
736 	 */
737 	/*
738 	 * If the previous action was a forward movement,
739 	 * don't clear the bottom line of the display;
740 	 * just print the prompt since the forward movement guarantees
741 	 * that we're in the right position to display the prompt.
742 	 * Clearing the line could cause a problem: for example, if the last
743 	 * line displayed ended at the right screen edge without a newline,
744 	 * then clearing would clear the last displayed line rather than
745 	 * the prompt line.
746 	 */
747 	if (!forw_prompt)
748 		clear_bot();
749 	clear_cmd();
750 	forw_prompt = 0;
751 	p = pr_string();
752 	if (is_filtering())
753 		putstr("& ");
754 	if (p == NULL || *p == '\0')
755 		putchr(':');
756 	else
757 	{
758 		at_enter(AT_STANDOUT);
759 		putstr(p);
760 		at_exit();
761 	}
762 	clear_eol();
763 }
764 
765 /*
766  * Display the less version message.
767  */
768 	public void
769 dispversion()
770 {
771 	PARG parg;
772 
773 	parg.p_string = version;
774 	error("less %s", &parg);
775 }
776 
777 /*
778  * Get command character.
779  * The character normally comes from the keyboard,
780  * but may come from ungotten characters
781  * (characters previously given to ungetcc or ungetsc).
782  */
783 	public int
784 getcc()
785 {
786 	if (ungot == NULL)
787 	{
788 		/*
789 		 * Normal case: no ungotten chars, so get one from the user.
790 		 */
791 		return (getchr());
792 	}
793 
794 	/*
795 	 * Return the next ungotten char.
796 	 */
797 	{
798 		struct ungot *ug = ungot;
799 		char c = ug->ug_char;
800 		int end_command = ug->ug_end_command;
801 		ungot = ug->ug_next;
802 		free(ug);
803 		if (end_command)
804 		{
805 			/*
806 			 * Command is incomplete, so try to complete it.
807 			 */
808 			switch (mca)
809 			{
810 			case A_DIGIT:
811 				/*
812 				 * We have a number but no command.  Treat as #g.
813 				 */
814 				return ('g');
815 
816 			case A_F_SEARCH:
817 			case A_B_SEARCH:
818 				/*
819 				 * We have "/string" but no newline.  Add the \n.
820 				 */
821 				return ('\n');
822 
823 			default:
824 				/*
825 				 * Some other incomplete command.  Let user complete it.
826 				 */
827 				return (getchr());
828 			}
829 		}
830 		return (c);
831 	}
832 }
833 
834 /*
835  * "Unget" a command character.
836  * The next getcc() will return this character.
837  */
838 	public void
839 ungetcc(c)
840 	int c;
841 {
842 	struct ungot *ug = (struct ungot *) ecalloc(1, sizeof(struct ungot));
843 
844 	ug->ug_char = (char) c;
845 	ug->ug_end_command = (c == CHAR_END_COMMAND);
846 	ug->ug_next = ungot;
847 	ungot = ug;
848 }
849 
850 /*
851  * Unget a whole string of command characters.
852  * The next sequence of getcc()'s will return this string.
853  */
854 	public void
855 ungetsc(s)
856 	char *s;
857 {
858 	char *p;
859 
860 	for (p = s + strlen(s) - 1;  p >= s;  p--)
861 		ungetcc(*p);
862 }
863 
864 /*
865  * Search for a pattern, possibly in multiple files.
866  * If SRCH_FIRST_FILE is set, begin searching at the first file.
867  * If SRCH_PAST_EOF is set, continue the search thru multiple files.
868  */
869 	static void
870 multi_search(pattern, n, silent)
871 	char *pattern;
872 	int n;
873 	int silent;
874 {
875 	int nomore;
876 	IFILE save_ifile;
877 	int changed_file;
878 
879 	changed_file = 0;
880 	save_ifile = save_curr_ifile();
881 
882 	if (search_type & SRCH_FIRST_FILE)
883 	{
884 		/*
885 		 * Start at the first (or last) file
886 		 * in the command line list.
887 		 */
888 		if (search_type & SRCH_FORW)
889 			nomore = edit_first();
890 		else
891 			nomore = edit_last();
892 		if (nomore)
893 		{
894 			unsave_ifile(save_ifile);
895 			return;
896 		}
897 		changed_file = 1;
898 		search_type &= ~SRCH_FIRST_FILE;
899 	}
900 
901 	for (;;)
902 	{
903 		n = search(search_type, pattern, n);
904 		/*
905 		 * The SRCH_NO_MOVE flag doesn't "stick": it gets cleared
906 		 * after being used once.  This allows "n" to work after
907 		 * using a /@@ search.
908 		 */
909 		search_type &= ~SRCH_NO_MOVE;
910 		if (n == 0)
911 		{
912 			/*
913 			 * Found it.
914 			 */
915 			unsave_ifile(save_ifile);
916 			return;
917 		}
918 
919 		if (n < 0)
920 			/*
921 			 * Some kind of error in the search.
922 			 * Error message has been printed by search().
923 			 */
924 			break;
925 
926 		if ((search_type & SRCH_PAST_EOF) == 0)
927 			/*
928 			 * We didn't find a match, but we're
929 			 * supposed to search only one file.
930 			 */
931 			break;
932 		/*
933 		 * Move on to the next file.
934 		 */
935 		if (search_type & SRCH_FORW)
936 			nomore = edit_next(1);
937 		else
938 			nomore = edit_prev(1);
939 		if (nomore)
940 			break;
941 		changed_file = 1;
942 	}
943 
944 	/*
945 	 * Didn't find it.
946 	 * Print an error message if we haven't already.
947 	 */
948 	if (n > 0 && !silent)
949 		error("Pattern not found", NULL_PARG);
950 
951 	if (changed_file)
952 	{
953 		/*
954 		 * Restore the file we were originally viewing.
955 		 */
956 		reedit_ifile(save_ifile);
957 	} else
958 	{
959 		unsave_ifile(save_ifile);
960 	}
961 }
962 
963 /*
964  * Forward forever, or until a highlighted line appears.
965  */
966 	static int
967 forw_loop(until_hilite)
968 	int until_hilite;
969 {
970 	POSITION curr_len;
971 
972 	if (ch_getflags() & CH_HELPFILE)
973 		return (A_NOACTION);
974 
975 	cmd_exec();
976 	jump_forw_buffered();
977 	curr_len = ch_length();
978 	highest_hilite = until_hilite ? curr_len : NULL_POSITION;
979 	ignore_eoi = 1;
980 	while (!sigs)
981 	{
982 		if (until_hilite && highest_hilite > curr_len)
983 		{
984 			bell();
985 			break;
986 		}
987 		make_display();
988 		forward(1, 0, 0);
989 	}
990 	ignore_eoi = 0;
991 	ch_set_eof();
992 
993 	/*
994 	 * This gets us back in "F mode" after processing
995 	 * a non-abort signal (e.g. window-change).
996 	 */
997 	if (sigs && !ABORT_SIGS())
998 		return (until_hilite ? A_F_UNTIL_HILITE : A_F_FOREVER);
999 
1000 	return (A_NOACTION);
1001 }
1002 
1003 /*
1004  * Main command processor.
1005  * Accept and execute commands until a quit command.
1006  */
1007 	public void
1008 commands()
1009 {
1010 	int c;
1011 	int action;
1012 	char *cbuf;
1013 	int newaction;
1014 	int save_search_type;
1015 	char *extra;
1016 	char tbuf[2];
1017 	PARG parg;
1018 	IFILE old_ifile;
1019 	IFILE new_ifile;
1020 	char *tagfile;
1021 
1022 	search_type = SRCH_FORW;
1023 	wscroll = (sc_height + 1) / 2;
1024 	newaction = A_NOACTION;
1025 
1026 	for (;;)
1027 	{
1028 		mca = 0;
1029 		cmd_accept();
1030 		number = 0;
1031 		curropt = NULL;
1032 
1033 		/*
1034 		 * See if any signals need processing.
1035 		 */
1036 		if (sigs)
1037 		{
1038 			psignals();
1039 			if (quitting)
1040 				quit(QUIT_SAVED_STATUS);
1041 		}
1042 
1043 		/*
1044 		 * See if window size changed, for systems that don't
1045 		 * generate SIGWINCH.
1046 		 */
1047 		check_winch();
1048 
1049 		/*
1050 		 * Display prompt and accept a character.
1051 		 */
1052 		cmd_reset();
1053 		prompt();
1054 		if (sigs)
1055 			continue;
1056 		if (newaction == A_NOACTION)
1057 			c = getcc();
1058 
1059 	again:
1060 		if (sigs)
1061 			continue;
1062 
1063 		if (newaction != A_NOACTION)
1064 		{
1065 			action = newaction;
1066 			newaction = A_NOACTION;
1067 		} else
1068 		{
1069 			/*
1070 			 * If we are in a multicharacter command, call mca_char.
1071 			 * Otherwise we call fcmd_decode to determine the
1072 			 * action to be performed.
1073 			 */
1074 			if (mca)
1075 				switch (mca_char(c))
1076 				{
1077 				case MCA_MORE:
1078 					/*
1079 					 * Need another character.
1080 					 */
1081 					c = getcc();
1082 					goto again;
1083 				case MCA_DONE:
1084 					/*
1085 					 * Command has been handled by mca_char.
1086 					 * Start clean with a prompt.
1087 					 */
1088 					continue;
1089 				case NO_MCA:
1090 					/*
1091 					 * Not a multi-char command
1092 					 * (at least, not anymore).
1093 					 */
1094 					break;
1095 				}
1096 
1097 			/*
1098 			 * Decode the command character and decide what to do.
1099 			 */
1100 			if (mca)
1101 			{
1102 				/*
1103 				 * We're in a multichar command.
1104 				 * Add the character to the command buffer
1105 				 * and display it on the screen.
1106 				 * If the user backspaces past the start
1107 				 * of the line, abort the command.
1108 				 */
1109 				if (cmd_char(c) == CC_QUIT || len_cmdbuf() == 0)
1110 					continue;
1111 				cbuf = get_cmdbuf();
1112 			} else
1113 			{
1114 				/*
1115 				 * Don't use cmd_char if we're starting fresh
1116 				 * at the beginning of a command, because we
1117 				 * don't want to echo the command until we know
1118 				 * it is a multichar command.  We also don't
1119 				 * want erase_char/kill_char to be treated
1120 				 * as line editing characters.
1121 				 */
1122 				tbuf[0] = c;
1123 				tbuf[1] = '\0';
1124 				cbuf = tbuf;
1125 			}
1126 			extra = NULL;
1127 			action = fcmd_decode(cbuf, &extra);
1128 			/*
1129 			 * If an "extra" string was returned,
1130 			 * process it as a string of command characters.
1131 			 */
1132 			if (extra != NULL)
1133 				ungetsc(extra);
1134 		}
1135 		/*
1136 		 * Clear the cmdbuf string.
1137 		 * (But not if we're in the prefix of a command,
1138 		 * because the partial command string is kept there.)
1139 		 */
1140 		if (action != A_PREFIX)
1141 			cmd_reset();
1142 
1143 		switch (action)
1144 		{
1145 		case A_DIGIT:
1146 			/*
1147 			 * First digit of a number.
1148 			 */
1149 			start_mca(A_DIGIT, ":", (void*)NULL, CF_QUIT_ON_ERASE);
1150 			goto again;
1151 
1152 		case A_F_WINDOW:
1153 			/*
1154 			 * Forward one window (and set the window size).
1155 			 */
1156 			if (number > 0)
1157 				swindow = (int) number;
1158 			/* FALLTHRU */
1159 		case A_F_SCREEN:
1160 			/*
1161 			 * Forward one screen.
1162 			 */
1163 			if (number <= 0)
1164 				number = get_swindow();
1165 			cmd_exec();
1166 			if (show_attn)
1167 				set_attnpos(bottompos);
1168 			forward((int) number, 0, 1);
1169 			break;
1170 
1171 		case A_B_WINDOW:
1172 			/*
1173 			 * Backward one window (and set the window size).
1174 			 */
1175 			if (number > 0)
1176 				swindow = (int) number;
1177 			/* FALLTHRU */
1178 		case A_B_SCREEN:
1179 			/*
1180 			 * Backward one screen.
1181 			 */
1182 			if (number <= 0)
1183 				number = get_swindow();
1184 			cmd_exec();
1185 			backward((int) number, 0, 1);
1186 			break;
1187 
1188 		case A_F_LINE:
1189 			/*
1190 			 * Forward N (default 1) line.
1191 			 */
1192 			if (number <= 0)
1193 				number = 1;
1194 			cmd_exec();
1195 			if (show_attn == OPT_ONPLUS && number > 1)
1196 				set_attnpos(bottompos);
1197 			forward((int) number, 0, 0);
1198 			break;
1199 
1200 		case A_B_LINE:
1201 			/*
1202 			 * Backward N (default 1) line.
1203 			 */
1204 			if (number <= 0)
1205 				number = 1;
1206 			cmd_exec();
1207 			backward((int) number, 0, 0);
1208 			break;
1209 
1210 		case A_FF_LINE:
1211 			/*
1212 			 * Force forward N (default 1) line.
1213 			 */
1214 			if (number <= 0)
1215 				number = 1;
1216 			cmd_exec();
1217 			if (show_attn == OPT_ONPLUS && number > 1)
1218 				set_attnpos(bottompos);
1219 			forward((int) number, 1, 0);
1220 			break;
1221 
1222 		case A_BF_LINE:
1223 			/*
1224 			 * Force backward N (default 1) line.
1225 			 */
1226 			if (number <= 0)
1227 				number = 1;
1228 			cmd_exec();
1229 			backward((int) number, 1, 0);
1230 			break;
1231 
1232 		case A_FF_SCREEN:
1233 			/*
1234 			 * Force forward one screen.
1235 			 */
1236 			if (number <= 0)
1237 				number = get_swindow();
1238 			cmd_exec();
1239 			if (show_attn == OPT_ONPLUS)
1240 				set_attnpos(bottompos);
1241 			forward((int) number, 1, 0);
1242 			break;
1243 
1244 		case A_F_FOREVER:
1245 			/*
1246 			 * Forward forever, ignoring EOF.
1247 			 */
1248 			if (show_attn)
1249 				set_attnpos(bottompos);
1250 			newaction = forw_loop(0);
1251 			break;
1252 
1253 		case A_F_UNTIL_HILITE:
1254 			newaction = forw_loop(1);
1255 			break;
1256 
1257 		case A_F_SCROLL:
1258 			/*
1259 			 * Forward N lines
1260 			 * (default same as last 'd' or 'u' command).
1261 			 */
1262 			if (number > 0)
1263 				wscroll = (int) number;
1264 			cmd_exec();
1265 			if (show_attn == OPT_ONPLUS)
1266 				set_attnpos(bottompos);
1267 			forward(wscroll, 0, 0);
1268 			break;
1269 
1270 		case A_B_SCROLL:
1271 			/*
1272 			 * Forward N lines
1273 			 * (default same as last 'd' or 'u' command).
1274 			 */
1275 			if (number > 0)
1276 				wscroll = (int) number;
1277 			cmd_exec();
1278 			backward(wscroll, 0, 0);
1279 			break;
1280 
1281 		case A_FREPAINT:
1282 			/*
1283 			 * Flush buffers, then repaint screen.
1284 			 * Don't flush the buffers on a pipe!
1285 			 */
1286 			clear_buffers();
1287 			/* FALLTHRU */
1288 		case A_REPAINT:
1289 			/*
1290 			 * Repaint screen.
1291 			 */
1292 			cmd_exec();
1293 			repaint();
1294 			break;
1295 
1296 		case A_GOLINE:
1297 			/*
1298 			 * Go to line N, default beginning of file.
1299 			 */
1300 			if (number <= 0)
1301 				number = 1;
1302 			cmd_exec();
1303 			jump_back(number);
1304 			break;
1305 
1306 		case A_PERCENT:
1307 			/*
1308 			 * Go to a specified percentage into the file.
1309 			 */
1310 			if (number < 0)
1311 			{
1312 				number = 0;
1313 				fraction = 0;
1314 			}
1315 			if (number > 100)
1316 			{
1317 				number = 100;
1318 				fraction = 0;
1319 			}
1320 			cmd_exec();
1321 			jump_percent((int) number, fraction);
1322 			break;
1323 
1324 		case A_GOEND:
1325 			/*
1326 			 * Go to line N, default end of file.
1327 			 */
1328 			cmd_exec();
1329 			if (number <= 0)
1330 				jump_forw();
1331 			else
1332 				jump_back(number);
1333 			break;
1334 
1335 		case A_GOEND_BUF:
1336 			/*
1337 			 * Go to line N, default last buffered byte.
1338 			 */
1339 			cmd_exec();
1340 			if (number <= 0)
1341 				jump_forw_buffered();
1342 			else
1343 				jump_back(number);
1344 			break;
1345 
1346 		case A_GOPOS:
1347 			/*
1348 			 * Go to a specified byte position in the file.
1349 			 */
1350 			cmd_exec();
1351 			if (number < 0)
1352 				number = 0;
1353 			jump_line_loc((POSITION) number, jump_sline);
1354 			break;
1355 
1356 		case A_STAT:
1357 			/*
1358 			 * Print file name, etc.
1359 			 */
1360 			if (ch_getflags() & CH_HELPFILE)
1361 				break;
1362 			cmd_exec();
1363 			parg.p_string = eq_message();
1364 			error("%s", &parg);
1365 			break;
1366 
1367 		case A_VERSION:
1368 			/*
1369 			 * Print version number, without the "@(#)".
1370 			 */
1371 			cmd_exec();
1372 			dispversion();
1373 			break;
1374 
1375 		case A_QUIT:
1376 			/*
1377 			 * Exit.
1378 			 */
1379 			if (curr_ifile != NULL_IFILE &&
1380 			    ch_getflags() & CH_HELPFILE)
1381 			{
1382 				/*
1383 				 * Quit while viewing the help file
1384 				 * just means return to viewing the
1385 				 * previous file.
1386 				 */
1387 				hshift = save_hshift;
1388 				bs_mode = save_bs_mode;
1389 				if (edit_prev(1) == 0)
1390 					break;
1391 			}
1392 			if (extra != NULL)
1393 				quit(*extra);
1394 			quit(QUIT_OK);
1395 			break;
1396 
1397 /*
1398  * Define abbreviation for a commonly used sequence below.
1399  */
1400 #define	DO_SEARCH() \
1401 			if (number <= 0) number = 1;	\
1402 			mca_search();			\
1403 			cmd_exec();			\
1404 			multi_search((char *)NULL, (int) number, 0);
1405 
1406 
1407 		case A_F_SEARCH:
1408 			/*
1409 			 * Search forward for a pattern.
1410 			 * Get the first char of the pattern.
1411 			 */
1412 			search_type = SRCH_FORW;
1413 			if (number <= 0)
1414 				number = 1;
1415 			mca_search();
1416 			c = getcc();
1417 			goto again;
1418 
1419 		case A_B_SEARCH:
1420 			/*
1421 			 * Search backward for a pattern.
1422 			 * Get the first char of the pattern.
1423 			 */
1424 			search_type = SRCH_BACK;
1425 			if (number <= 0)
1426 				number = 1;
1427 			mca_search();
1428 			c = getcc();
1429 			goto again;
1430 
1431 		case A_FILTER:
1432 #if HILITE_SEARCH
1433 			search_type = SRCH_FORW | SRCH_FILTER;
1434 			mca_search();
1435 			c = getcc();
1436 			goto again;
1437 #else
1438 			error("Command not available", NULL_PARG);
1439 			break;
1440 #endif
1441 
1442 		case A_AGAIN_SEARCH:
1443 			/*
1444 			 * Repeat previous search.
1445 			 */
1446 			DO_SEARCH();
1447 			break;
1448 
1449 		case A_T_AGAIN_SEARCH:
1450 			/*
1451 			 * Repeat previous search, multiple files.
1452 			 */
1453 			search_type |= SRCH_PAST_EOF;
1454 			DO_SEARCH();
1455 			break;
1456 
1457 		case A_REVERSE_SEARCH:
1458 			/*
1459 			 * Repeat previous search, in reverse direction.
1460 			 */
1461 			save_search_type = search_type;
1462 			search_type = SRCH_REVERSE(search_type);
1463 			DO_SEARCH();
1464 			search_type = save_search_type;
1465 			break;
1466 
1467 		case A_T_REVERSE_SEARCH:
1468 			/*
1469 			 * Repeat previous search,
1470 			 * multiple files in reverse direction.
1471 			 */
1472 			save_search_type = search_type;
1473 			search_type = SRCH_REVERSE(search_type);
1474 			search_type |= SRCH_PAST_EOF;
1475 			DO_SEARCH();
1476 			search_type = save_search_type;
1477 			break;
1478 
1479 		case A_UNDO_SEARCH:
1480 			undo_search();
1481 			break;
1482 
1483 		case A_HELP:
1484 			/*
1485 			 * Help.
1486 			 */
1487 			if (ch_getflags() & CH_HELPFILE)
1488 				break;
1489 			cmd_exec();
1490 			save_hshift = hshift;
1491 			hshift = 0;
1492 			save_bs_mode = bs_mode;
1493 			bs_mode = BS_SPECIAL;
1494 			(void) edit(FAKE_HELPFILE);
1495 			break;
1496 
1497 		case A_EXAMINE:
1498 #if EXAMINE
1499 			/*
1500 			 * Edit a new file.  Get the filename.
1501 			 */
1502 			if (secure)
1503 			{
1504 				error("Command not available", NULL_PARG);
1505 				break;
1506 			}
1507 			start_mca(A_EXAMINE, "Examine: ", ml_examine, 0);
1508 			c = getcc();
1509 			goto again;
1510 #else
1511 			error("Command not available", NULL_PARG);
1512 			break;
1513 #endif
1514 
1515 		case A_VISUAL:
1516 			/*
1517 			 * Invoke an editor on the input file.
1518 			 */
1519 #if EDITOR
1520 			if (secure)
1521 			{
1522 				error("Command not available", NULL_PARG);
1523 				break;
1524 			}
1525 			if (ch_getflags() & CH_HELPFILE)
1526 				break;
1527 			if (strcmp(get_filename(curr_ifile), "-") == 0)
1528 			{
1529 				error("Cannot edit standard input", NULL_PARG);
1530 				break;
1531 			}
1532 			if (curr_altfilename != NULL)
1533 			{
1534 				error("WARNING: This file was viewed via LESSOPEN",
1535 					NULL_PARG);
1536 			}
1537 			start_mca(A_SHELL, "!", ml_shell, 0);
1538 			/*
1539 			 * Expand the editor prototype string
1540 			 * and pass it to the system to execute.
1541 			 * (Make sure the screen is displayed so the
1542 			 * expansion of "+%lm" works.)
1543 			 */
1544 			make_display();
1545 			cmd_exec();
1546 			lsystem(pr_expand(editproto, 0), (char*)NULL);
1547 			break;
1548 #else
1549 			error("Command not available", NULL_PARG);
1550 			break;
1551 #endif
1552 
1553 		case A_NEXT_FILE:
1554 			/*
1555 			 * Examine next file.
1556 			 */
1557 #if TAGS
1558 			if (ntags())
1559 			{
1560 				error("No next file", NULL_PARG);
1561 				break;
1562 			}
1563 #endif
1564 			if (number <= 0)
1565 				number = 1;
1566 			if (edit_next((int) number))
1567 			{
1568 				if (get_quit_at_eof() && eof_displayed() &&
1569 				    !(ch_getflags() & CH_HELPFILE))
1570 					quit(QUIT_OK);
1571 				parg.p_string = (number > 1) ? "(N-th) " : "";
1572 				error("No %snext file", &parg);
1573 			}
1574 			break;
1575 
1576 		case A_PREV_FILE:
1577 			/*
1578 			 * Examine previous file.
1579 			 */
1580 #if TAGS
1581 			if (ntags())
1582 			{
1583 				error("No previous file", NULL_PARG);
1584 				break;
1585 			}
1586 #endif
1587 			if (number <= 0)
1588 				number = 1;
1589 			if (edit_prev((int) number))
1590 			{
1591 				parg.p_string = (number > 1) ? "(N-th) " : "";
1592 				error("No %sprevious file", &parg);
1593 			}
1594 			break;
1595 
1596 		case A_NEXT_TAG:
1597 #if TAGS
1598 			if (number <= 0)
1599 				number = 1;
1600 			tagfile = nexttag((int) number);
1601 			if (tagfile == NULL)
1602 			{
1603 				error("No next tag", NULL_PARG);
1604 				break;
1605 			}
1606 			if (edit(tagfile) == 0)
1607 			{
1608 				POSITION pos = tagsearch();
1609 				if (pos != NULL_POSITION)
1610 					jump_loc(pos, jump_sline);
1611 			}
1612 #else
1613 			error("Command not available", NULL_PARG);
1614 #endif
1615 			break;
1616 
1617 		case A_PREV_TAG:
1618 #if TAGS
1619 			if (number <= 0)
1620 				number = 1;
1621 			tagfile = prevtag((int) number);
1622 			if (tagfile == NULL)
1623 			{
1624 				error("No previous tag", NULL_PARG);
1625 				break;
1626 			}
1627 			if (edit(tagfile) == 0)
1628 			{
1629 				POSITION pos = tagsearch();
1630 				if (pos != NULL_POSITION)
1631 					jump_loc(pos, jump_sline);
1632 			}
1633 #else
1634 			error("Command not available", NULL_PARG);
1635 #endif
1636 			break;
1637 
1638 		case A_INDEX_FILE:
1639 			/*
1640 			 * Examine a particular file.
1641 			 */
1642 			if (number <= 0)
1643 				number = 1;
1644 			if (edit_index((int) number))
1645 				error("No such file", NULL_PARG);
1646 			break;
1647 
1648 		case A_REMOVE_FILE:
1649 			if (ch_getflags() & CH_HELPFILE)
1650 				break;
1651 			old_ifile = curr_ifile;
1652 			new_ifile = getoff_ifile(curr_ifile);
1653 			if (new_ifile == NULL_IFILE)
1654 			{
1655 				bell();
1656 				break;
1657 			}
1658 			if (edit_ifile(new_ifile) != 0)
1659 			{
1660 				reedit_ifile(old_ifile);
1661 				break;
1662 			}
1663 			del_ifile(old_ifile);
1664 			break;
1665 
1666 		case A_OPT_TOGGLE:
1667 			optflag = OPT_TOGGLE;
1668 			optgetname = FALSE;
1669 			mca_opt_toggle();
1670 			c = getcc();
1671 			goto again;
1672 
1673 		case A_DISP_OPTION:
1674 			/*
1675 			 * Report a flag setting.
1676 			 */
1677 			optflag = OPT_NO_TOGGLE;
1678 			optgetname = FALSE;
1679 			mca_opt_toggle();
1680 			c = getcc();
1681 			goto again;
1682 
1683 		case A_FIRSTCMD:
1684 			/*
1685 			 * Set an initial command for new files.
1686 			 */
1687 			start_mca(A_FIRSTCMD, "+", (void*)NULL, 0);
1688 			c = getcc();
1689 			goto again;
1690 
1691 		case A_SHELL:
1692 			/*
1693 			 * Shell escape.
1694 			 */
1695 #if SHELL_ESCAPE
1696 			if (secure)
1697 			{
1698 				error("Command not available", NULL_PARG);
1699 				break;
1700 			}
1701 			start_mca(A_SHELL, "!", ml_shell, 0);
1702 			c = getcc();
1703 			goto again;
1704 #else
1705 			error("Command not available", NULL_PARG);
1706 			break;
1707 #endif
1708 
1709 		case A_SETMARK:
1710 			/*
1711 			 * Set a mark.
1712 			 */
1713 			if (ch_getflags() & CH_HELPFILE)
1714 				break;
1715 			start_mca(A_SETMARK, "mark: ", (void*)NULL, 0);
1716 			c = getcc();
1717 			if (c == erase_char || c == erase2_char ||
1718 			    c == kill_char || c == '\n' || c == '\r')
1719 				break;
1720 			setmark(c);
1721 			break;
1722 
1723 		case A_GOMARK:
1724 			/*
1725 			 * Go to a mark.
1726 			 */
1727 			start_mca(A_GOMARK, "goto mark: ", (void*)NULL, 0);
1728 			c = getcc();
1729 			if (c == erase_char || c == erase2_char ||
1730 			    c == kill_char || c == '\n' || c == '\r')
1731 				break;
1732 			cmd_exec();
1733 			gomark(c);
1734 			break;
1735 
1736 		case A_PIPE:
1737 #if PIPEC
1738 			if (secure)
1739 			{
1740 				error("Command not available", NULL_PARG);
1741 				break;
1742 			}
1743 			start_mca(A_PIPE, "|mark: ", (void*)NULL, 0);
1744 			c = getcc();
1745 			if (c == erase_char || c == erase2_char || c == kill_char)
1746 				break;
1747 			if (c == '\n' || c == '\r')
1748 				c = '.';
1749 			if (badmark(c))
1750 				break;
1751 			pipec = c;
1752 			start_mca(A_PIPE, "!", ml_shell, 0);
1753 			c = getcc();
1754 			goto again;
1755 #else
1756 			error("Command not available", NULL_PARG);
1757 			break;
1758 #endif
1759 
1760 		case A_B_BRACKET:
1761 		case A_F_BRACKET:
1762 			start_mca(action, "Brackets: ", (void*)NULL, 0);
1763 			c = getcc();
1764 			goto again;
1765 
1766 		case A_LSHIFT:
1767 			if (number > 0)
1768 				shift_count = number;
1769 			else
1770 				number = (shift_count > 0) ?
1771 					shift_count : sc_width / 2;
1772 			if (number > hshift)
1773 				number = hshift;
1774 			hshift -= number;
1775 			screen_trashed = 1;
1776 			break;
1777 
1778 		case A_RSHIFT:
1779 			if (number > 0)
1780 				shift_count = number;
1781 			else
1782 				number = (shift_count > 0) ?
1783 					shift_count : sc_width / 2;
1784 			hshift += number;
1785 			screen_trashed = 1;
1786 			break;
1787 
1788 		case A_LLSHIFT:
1789 			hshift = 0;
1790 			screen_trashed = 1;
1791 			break;
1792 
1793 		case A_RRSHIFT:
1794 			hshift = rrshift();
1795 			screen_trashed = 1;
1796 			break;
1797 
1798 		case A_PREFIX:
1799 			/*
1800 			 * The command is incomplete (more chars are needed).
1801 			 * Display the current char, so the user knows
1802 			 * what's going on, and get another character.
1803 			 */
1804 			if (mca != A_PREFIX)
1805 			{
1806 				cmd_reset();
1807 				start_mca(A_PREFIX, " ", (void*)NULL,
1808 					CF_QUIT_ON_ERASE);
1809 				(void) cmd_char(c);
1810 			}
1811 			c = getcc();
1812 			goto again;
1813 
1814 		case A_NOACTION:
1815 			break;
1816 
1817 		default:
1818 			bell();
1819 			break;
1820 		}
1821 	}
1822 }
1823