xref: /netbsd-src/usr.bin/msgs/msgs.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: msgs.c,v 1.8 1997/05/17 20:09:26 pk Exp $	*/
2 
3 /*-
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1980, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)msgs.c	8.2 (Berkeley) 4/28/95";
45 #else
46 static char rcsid[] = "$NetBSD: msgs.c,v 1.8 1997/05/17 20:09:26 pk Exp $";
47 #endif
48 #endif /* not lint */
49 
50 /*
51  * msgs - a user bulletin board program
52  *
53  * usage:
54  *	msgs [fhlopqr] [[-]number]	to read messages
55  *	msgs -s				to place messages
56  *	msgs -c [-days]			to clean up the bulletin board
57  *
58  * prompt commands are:
59  *	y	print message
60  *	n	flush message, go to next message
61  *	q	flush message, quit
62  *	p	print message, turn on 'pipe thru more' mode
63  *	P	print message, turn off 'pipe thru more' mode
64  *	-	reprint last message
65  *	s[-][<num>] [<filename>]	save message
66  *	m[-][<num>]	mail with message in temp mbox
67  *	x	exit without flushing this message
68  *	<num>	print message number <num>
69  */
70 
71 #define V7		/* will look for TERM in the environment */
72 #define OBJECT		/* will object to messages without Subjects */
73 #define REJECT	/* will reject messages without Subjects
74 			   (OBJECT must be defined also) */
75 /* #define UNBUFFERED	/* use unbuffered output */
76 
77 #include <sys/param.h>
78 #include <sys/ioctl.h>
79 #include <sys/stat.h>
80 #include <dirent.h>
81 #include <ctype.h>
82 #include <errno.h>
83 #include <pwd.h>
84 #include <setjmp.h>
85 #include <signal.h>
86 #include <stdio.h>
87 #include <stdlib.h>
88 #include <string.h>
89 #include <termios.h>
90 #include <time.h>
91 #include <unistd.h>
92 #include "pathnames.h"
93 
94 #define CMODE	0664		/* bounds file creation mode */
95 #define NO	0
96 #define YES	1
97 #define SUPERUSER	0	/* superuser uid */
98 #define DAEMON		1	/* daemon uid */
99 #define NLINES	24		/* default number of lines/crt screen */
100 #define NDAYS	21		/* default keep time for messages */
101 #define DAYS	*24*60*60	/* seconds/day */
102 #define MSGSRC	".msgsrc"	/* user's rc file */
103 #define BOUNDS	"bounds"	/* message bounds file */
104 #define NEXT	"Next message? [yq]"
105 #define MORE	"More? [ynq]"
106 #define NOMORE	"(No more) [q] ?"
107 
108 typedef	char	bool;
109 
110 FILE	*msgsrc;
111 FILE	*newmsg;
112 char	*sep = "-";
113 char	inbuf[BUFSIZ];
114 char	fname[128];
115 char	cmdbuf[128];
116 char	subj[128];
117 char	from[128];
118 char	date[128];
119 char	*ptr;
120 char	*in;
121 bool	local;
122 bool	ruptible;
123 bool	totty;
124 bool	seenfrom;
125 bool	seensubj;
126 bool	blankline;
127 bool	printing = NO;
128 bool	mailing = NO;
129 bool	quitit = NO;
130 bool	sending = NO;
131 bool	intrpflg = NO;
132 bool	restricted = NO;
133 int	uid;
134 int	msg;
135 int	prevmsg;
136 int	lct;
137 int	nlines;
138 int	Lpp = 0;
139 time_t	t;
140 time_t	keep;
141 
142 char	*mktemp();
143 char	*nxtfld();
144 void	onintr();
145 void	onsusp();
146 
147 /* option initialization */
148 bool	hdrs = NO;
149 bool	qopt = NO;
150 bool	hush = NO;
151 bool	send_msg = NO;
152 bool	locomode = NO;
153 bool	use_pager = NO;
154 bool	clean = NO;
155 bool	lastcmd = NO;
156 jmp_buf	tstpbuf;
157 
158 main(argc, argv)
159 int argc; char *argv[];
160 {
161 	bool newrc, already;
162 	int rcfirst = 0;		/* first message to print (from .rc) */
163 	int rcback = 0;			/* amount to back off of rcfirst */
164 	int firstmsg, nextmsg, lastmsg = 0;
165 	int blast = 0;
166 	FILE *bounds;
167 
168 #ifdef UNBUFFERED
169 	setbuf(stdout, NULL);
170 #endif
171 
172 	time(&t);
173 	setuid(uid = getuid());
174 	ruptible = (signal(SIGINT, SIG_IGN) == SIG_DFL);
175 	if (ruptible)
176 		signal(SIGINT, SIG_DFL);
177 
178 	argc--, argv++;
179 	while (argc > 0) {
180 		if (isdigit(argv[0][0])) {	/* starting message # */
181 			rcfirst = atoi(argv[0]);
182 		}
183 		else if (isdigit(argv[0][1])) {	/* backward offset */
184 			rcback = atoi( &( argv[0][1] ) );
185 		}
186 		else {
187 			ptr = *argv;
188 			while (*ptr) switch (*ptr++) {
189 
190 			case '-':
191 				break;
192 
193 			case 'c':
194 				if (uid != SUPERUSER && uid != DAEMON) {
195 					fprintf(stderr, "Sorry\n");
196 					exit(1);
197 				}
198 				clean = YES;
199 				break;
200 
201 			case 'f':		/* silently */
202 				hush = YES;
203 				break;
204 
205 			case 'h':		/* headers only */
206 				hdrs = YES;
207 				break;
208 
209 			case 'l':		/* local msgs only */
210 				locomode = YES;
211 				break;
212 
213 			case 'o':		/* option to save last message */
214 				lastcmd = YES;
215 				break;
216 
217 			case 'p':		/* pipe thru 'more' during long msgs */
218 				use_pager = YES;
219 				break;
220 
221 			case 'q':		/* query only */
222 				qopt = YES;
223 				break;
224 
225                         case 'r':               /* restricted */
226                                 restricted = YES;
227                                 break;
228 
229 
230 			case 's':		/* sending TO msgs */
231 				send_msg = YES;
232 				break;
233 
234 			default:
235 				fprintf(stderr,
236 					"usage: msgs [fhlopqr] [[-]number]\n");
237 				exit(1);
238 			}
239 		}
240 		argc--, argv++;
241 	}
242 
243 	/*
244 	 * determine current message bounds
245 	 */
246 	sprintf(fname, "%s/%s", _PATH_MSGS, BOUNDS);
247 	bounds = fopen(fname, "r");
248 
249 	if (bounds != NULL) {
250 		fscanf(bounds, "%d %d\n", &firstmsg, &lastmsg);
251 		fclose(bounds);
252 		blast = lastmsg;	/* save upper bound */
253 	}
254 
255 	if (clean)
256 		keep = t - (rcback? rcback : NDAYS) DAYS;
257 
258 	if (clean || bounds == NULL) {	/* relocate message bounds */
259 		struct dirent *dp;
260 		struct stat stbuf;
261 		bool seenany = NO;
262 		DIR	*dirp;
263 
264 		dirp = opendir(_PATH_MSGS);
265 		if (dirp == NULL) {
266 			perror(_PATH_MSGS);
267 			exit(errno);
268 		}
269 		chmod(fname, CMODE);
270 
271 		firstmsg = 32767;
272 		lastmsg = 0;
273 
274 		for (dp = readdir(dirp); dp != NULL; dp = readdir(dirp)){
275 			register char *cp = dp->d_name;
276 			register int i = 0;
277 
278 			if (dp->d_ino == 0)
279 				continue;
280 			if (dp->d_namlen == 0)
281 				continue;
282 
283 			if (clean)
284 				sprintf(inbuf, "%s/%s", _PATH_MSGS, cp);
285 
286 			while (isdigit(*cp))
287 				i = i * 10 + *cp++ - '0';
288 			if (*cp)
289 				continue;	/* not a message! */
290 
291 			if (clean) {
292 				if (stat(inbuf, &stbuf) != 0)
293 					continue;
294 				if (stbuf.st_mtime < keep
295 				    && stbuf.st_mode&S_IWRITE) {
296 					unlink(inbuf);
297 					continue;
298 				}
299 			}
300 
301 			if (i > lastmsg)
302 				lastmsg = i;
303 			if (i < firstmsg)
304 				firstmsg = i;
305 			seenany = YES;
306 		}
307 		closedir(dirp);
308 
309 		if (!seenany) {
310 			if (blast != 0)	/* never lower the upper bound! */
311 				lastmsg = blast;
312 			firstmsg = lastmsg + 1;
313 		}
314 		else if (blast > lastmsg)
315 			lastmsg = blast;
316 
317 		if (!send_msg) {
318 			bounds = fopen(fname, "w");
319 			if (bounds == NULL) {
320 				perror(fname);
321 				exit(errno);
322 			}
323 			chmod(fname, CMODE);
324 			fprintf(bounds, "%d %d\n", firstmsg, lastmsg);
325 			fclose(bounds);
326 		}
327 	}
328 
329 	if (send_msg) {
330 		/*
331 		 * Send mode - place msgs in _PATH_MSGS
332 		 */
333 		bounds = fopen(fname, "w");
334 		if (bounds == NULL) {
335 			perror(fname);
336 			exit(errno);
337 		}
338 
339 		nextmsg = lastmsg + 1;
340 		sprintf(fname, "%s/%d", _PATH_MSGS, nextmsg);
341 		newmsg = fopen(fname, "w");
342 		if (newmsg == NULL) {
343 			perror(fname);
344 			exit(errno);
345 		}
346 		chmod(fname, 0644);
347 
348 		fprintf(bounds, "%d %d\n", firstmsg, nextmsg);
349 		fclose(bounds);
350 
351 		sending = YES;
352 		if (ruptible)
353 			signal(SIGINT, onintr);
354 
355 		if (isatty(fileno(stdin))) {
356 			ptr = getpwuid(uid)->pw_name;
357 			printf("Message %d:\nFrom %s %sSubject: ",
358 				nextmsg, ptr, ctime(&t));
359 			fflush(stdout);
360 			fgets(inbuf, sizeof inbuf, stdin);
361 			putchar('\n');
362 			fflush(stdout);
363 			fprintf(newmsg, "From %s %sSubject: %s\n",
364 				ptr, ctime(&t), inbuf);
365 			blankline = seensubj = YES;
366 		}
367 		else
368 			blankline = seensubj = NO;
369 		for (;;) {
370 			fgets(inbuf, sizeof inbuf, stdin);
371 			if (feof(stdin) || ferror(stdin))
372 				break;
373 			blankline = (blankline || (inbuf[0] == '\n'));
374 			seensubj = (seensubj || (!blankline && (strncmp(inbuf, "Subj", 4) == 0)));
375 			fputs(inbuf, newmsg);
376 		}
377 #ifdef OBJECT
378 		if (!seensubj) {
379 			printf("NOTICE: Messages should have a Subject field!\n");
380 #ifdef REJECT
381 			unlink(fname);
382 #endif
383 			exit(1);
384 		}
385 #endif
386 		exit(ferror(stdin));
387 	}
388 	if (clean)
389 		exit(0);
390 
391 	/*
392 	 * prepare to display messages
393 	 */
394 	totty = (isatty(fileno(stdout)) != 0);
395 	use_pager = use_pager && totty;
396 
397 	sprintf(fname, "%s/%s", getenv("HOME"), MSGSRC);
398 	msgsrc = fopen(fname, "r");
399 	if (msgsrc) {
400 		newrc = NO;
401                 fscanf(msgsrc, "%d\n", &nextmsg);
402                 fclose(msgsrc);
403                 if (nextmsg > lastmsg+1) {
404 			printf("Warning: bounds have been reset (%d, %d)\n",
405 				firstmsg, lastmsg);
406 			truncate(fname, (off_t)0);
407 			newrc = YES;
408 		}
409 		else if (!rcfirst)
410 			rcfirst = nextmsg - rcback;
411 	}
412         else
413         	newrc = YES;
414         msgsrc = fopen(fname, "r+");
415         if (msgsrc == NULL)
416                msgsrc = fopen(fname, "w");
417 	if (msgsrc == NULL) {
418 		perror(fname);
419 		exit(errno);
420 	}
421 	if (rcfirst) {
422 		if (rcfirst > lastmsg+1) {
423 			printf("Warning: the last message is number %d.\n",
424 				lastmsg);
425 			rcfirst = nextmsg;
426 		}
427 		if (rcfirst > firstmsg)
428 			firstmsg = rcfirst;	/* don't set below first msg */
429 	}
430 	if (newrc) {
431 		nextmsg = firstmsg;
432 		fseek(msgsrc, 0L, 0);
433 		fprintf(msgsrc, "%d\n", nextmsg);
434 		fflush(msgsrc);
435 	}
436 
437 #ifdef V7
438 	if (totty) {
439 		struct winsize win;
440 		if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1)
441 			Lpp = win.ws_row;
442 		if (Lpp <= 0) {
443 			if (tgetent(inbuf, getenv("TERM")) <= 0
444 			    || (Lpp = tgetnum("li")) <= 0) {
445 				Lpp = NLINES;
446 			}
447 		}
448 	}
449 #endif
450 	Lpp -= 6;	/* for headers, etc. */
451 
452 	already = NO;
453 	prevmsg = firstmsg;
454 	printing = YES;
455 	if (ruptible)
456 		signal(SIGINT, onintr);
457 
458 	/*
459 	 * Main program loop
460 	 */
461 	for (msg = firstmsg; msg <= lastmsg; msg++) {
462 
463 		sprintf(fname, "%s/%d", _PATH_MSGS, msg);
464 		newmsg = fopen(fname, "r");
465 		if (newmsg == NULL)
466 			continue;
467 
468 		gfrsub(newmsg);		/* get From and Subject fields */
469 		if (locomode && !local) {
470 			fclose(newmsg);
471 			continue;
472 		}
473 
474 		if (qopt) {	/* This has to be located here */
475 			printf("There are new messages.\n");
476 			exit(0);
477 		}
478 
479 		if (already && !hdrs)
480 			putchar('\n');
481 
482 		/*
483 		 * Print header
484 		 */
485 		if (totty)
486 			signal(SIGTSTP, onsusp);
487 		(void) setjmp(tstpbuf);
488 		already = YES;
489 		nlines = 2;
490 		if (seenfrom) {
491 			printf("Message %d:\nFrom %s %s", msg, from, date);
492 			nlines++;
493 		}
494 		if (seensubj) {
495 			printf("Subject: %s", subj);
496 			nlines++;
497 		}
498 		else {
499 			if (seenfrom) {
500 				putchar('\n');
501 				nlines++;
502 			}
503 			while (nlines < 6
504 			    && fgets(inbuf, sizeof inbuf, newmsg)
505 			    && inbuf[0] != '\n') {
506 				fputs(inbuf, stdout);
507 				nlines++;
508 			}
509 		}
510 
511 		lct = linecnt(newmsg);
512 		if (lct)
513 			printf("(%d%slines) ", lct, seensubj? " " : " more ");
514 
515 		if (hdrs) {
516 			printf("\n-----\n");
517 			fclose(newmsg);
518 			continue;
519 		}
520 
521 		/*
522 		 * Ask user for command
523 		 */
524 		if (totty)
525 			ask(lct? MORE : (msg==lastmsg? NOMORE : NEXT));
526 		else
527 			inbuf[0] = 'y';
528 		if (totty)
529 			signal(SIGTSTP, SIG_DFL);
530 cmnd:
531 		in = inbuf;
532 		switch (*in) {
533 			case 'x':
534 			case 'X':
535 				exit(0);
536 
537 			case 'q':
538 			case 'Q':
539 				quitit = YES;
540 				printf("--Postponed--\n");
541 				exit(0);
542 				/* intentional fall-thru */
543 			case 'n':
544 			case 'N':
545 				if (msg >= nextmsg) sep = "Flushed";
546 				prevmsg = msg;
547 				break;
548 
549 			case 'p':
550 			case 'P':
551 				use_pager = (*in++ == 'p');
552 				/* intentional fallthru */
553 			case '\n':
554 			case 'y':
555 			default:
556 				if (*in == '-') {
557 					msg = prevmsg-1;
558 					sep = "replay";
559 					break;
560 				}
561 				if (isdigit(*in)) {
562 					msg = next(in);
563 					sep = in;
564 					break;
565 				}
566 
567 				prmesg(nlines + lct + (seensubj? 1 : 0));
568 				prevmsg = msg;
569 
570 		}
571 
572 		printf("--%s--\n", sep);
573 		sep = "-";
574 		if (msg >= nextmsg) {
575 			nextmsg = msg + 1;
576 			fseek(msgsrc, 0L, 0);
577 			fprintf(msgsrc, "%d\n", nextmsg);
578 			fflush(msgsrc);
579 		}
580 		if (newmsg)
581 			fclose(newmsg);
582 		if (quitit)
583 			break;
584 	}
585 
586 	/*
587 	 * Make sure .rc file gets updated
588 	 */
589 	if (--msg >= nextmsg) {
590 		nextmsg = msg + 1;
591 		fseek(msgsrc, 0L, 0);
592 		fprintf(msgsrc, "%d\n", nextmsg);
593 		fflush(msgsrc);
594 	}
595 	if (already && !quitit && lastcmd && totty) {
596 		/*
597 		 * save or reply to last message?
598 		 */
599 		msg = prevmsg;
600 		ask(NOMORE);
601 		if (inbuf[0] == '-' || isdigit(inbuf[0]))
602 			goto cmnd;
603 	}
604 	if (!(already || hush || qopt))
605 		printf("No new messages.\n");
606 	exit(0);
607 }
608 
609 prmesg(length)
610 int length;
611 {
612 	FILE *outf;
613 	char *env_pager;
614 
615 	if (use_pager && length > Lpp) {
616 		signal(SIGPIPE, SIG_IGN);
617 		signal(SIGQUIT, SIG_IGN);
618                 if ((env_pager = getenv("PAGER")) == NULL) {
619                         sprintf(cmdbuf, _PATH_PAGER, Lpp);
620                 } else {
621                         strcpy(cmdbuf, env_pager);
622                 }
623 		outf = popen(cmdbuf, "w");
624 		if (!outf)
625 			outf = stdout;
626 		else
627 			setbuf(outf, (char *)NULL);
628 	}
629 	else
630 		outf = stdout;
631 
632 	if (seensubj)
633 		putc('\n', outf);
634 
635 	while (fgets(inbuf, sizeof inbuf, newmsg)) {
636 		fputs(inbuf, outf);
637 		if (ferror(outf)) {
638 			clearerr(outf);
639 			break;
640 		}
641 	}
642 
643 	if (outf != stdout) {
644 		pclose(outf);
645 		signal(SIGPIPE, SIG_DFL);
646 		signal(SIGQUIT, SIG_DFL);
647 	}
648 	else {
649 		fflush(stdout);
650 	}
651 
652 	/* trick to force wait on output */
653 	tcdrain(fileno(stdout));
654 }
655 
656 void
657 onintr()
658 {
659 	signal(SIGINT, onintr);
660 	if (mailing)
661 		unlink(fname);
662 	if (sending) {
663 		unlink(fname);
664 		puts("--Killed--");
665 		exit(1);
666 	}
667 	if (printing) {
668 		putchar('\n');
669 		if (hdrs)
670 			exit(0);
671 		sep = "Interrupt";
672 		if (newmsg)
673 			fseek(newmsg, 0L, 2);
674 		intrpflg = YES;
675 	}
676 }
677 
678 /*
679  * We have just gotten a susp.  Suspend and prepare to resume.
680  */
681 void
682 onsusp()
683 {
684 
685 	signal(SIGTSTP, SIG_DFL);
686 	sigsetmask(0);
687 	kill(0, SIGTSTP);
688 	signal(SIGTSTP, onsusp);
689 	if (!mailing)
690 		longjmp(tstpbuf, 0);
691 }
692 
693 linecnt(f)
694 FILE *f;
695 {
696 	off_t oldpos = ftell(f);
697 	int l = 0;
698 	char lbuf[BUFSIZ];
699 
700 	while (fgets(lbuf, sizeof lbuf, f))
701 		l++;
702 	clearerr(f);
703 	fseek(f, oldpos, 0);
704 	return (l);
705 }
706 
707 next(buf)
708 char *buf;
709 {
710 	int i;
711 	sscanf(buf, "%d", &i);
712 	sprintf(buf, "Goto %d", i);
713 	return(--i);
714 }
715 
716 ask(prompt)
717 char *prompt;
718 {
719 	char	inch;
720 	int	n, cmsg;
721 	off_t	oldpos;
722 	FILE	*cpfrom, *cpto;
723 
724 	printf("%s ", prompt);
725 	fflush(stdout);
726 	intrpflg = NO;
727 	(void) fgets(inbuf, sizeof inbuf, stdin);
728 	if ((n = strlen(inbuf)) > 0 && inbuf[n - 1] == '\n')
729 		inbuf[n - 1] = '\0';
730 	if (intrpflg)
731 		inbuf[0] = 'x';
732 
733 	/*
734 	 * Handle 'mail' and 'save' here.
735 	 */
736         if (((inch = inbuf[0]) == 's' || inch == 'm') && !restricted) {
737 		if (inbuf[1] == '-')
738 			cmsg = prevmsg;
739 		else if (isdigit(inbuf[1]))
740 			cmsg = atoi(&inbuf[1]);
741 		else
742 			cmsg = msg;
743 		sprintf(fname, "%s/%d", _PATH_MSGS, cmsg);
744 
745 		oldpos = ftell(newmsg);
746 
747 		cpfrom = fopen(fname, "r");
748 		if (!cpfrom) {
749 			printf("Message %d not found\n", cmsg);
750 			ask (prompt);
751 			return;
752 		}
753 
754 		if (inch == 's') {
755 			in = nxtfld(inbuf);
756 			if (*in) {
757 				for (n=0; in[n] > ' '; n++) { /* sizeof fname? */
758 					fname[n] = in[n];
759 				}
760 				fname[n] = '\0';
761 			}
762 			else
763 				strcpy(fname, "Messages");
764 		}
765 		else {
766 			strcpy(fname, _PATH_TMP);
767 			mktemp(fname);
768 			sprintf(cmdbuf, _PATH_MAIL, fname);
769 			mailing = YES;
770 		}
771 		cpto = fopen(fname, "a");
772 		if (!cpto) {
773 			perror(fname);
774 			mailing = NO;
775 			fseek(newmsg, oldpos, 0);
776 			ask(prompt);
777 			return;
778 		}
779 
780 		while (n = fread(inbuf, 1, sizeof inbuf, cpfrom))
781 			fwrite(inbuf, 1, n, cpto);
782 
783 		fclose(cpfrom);
784 		fclose(cpto);
785 		fseek(newmsg, oldpos, 0);	/* reposition current message */
786 		if (inch == 's')
787 			printf("Message %d saved in \"%s\"\n", cmsg, fname);
788 		else {
789 			system(cmdbuf);
790 			unlink(fname);
791 			mailing = NO;
792 		}
793 		ask(prompt);
794 	}
795 }
796 
797 gfrsub(infile)
798 FILE *infile;
799 {
800 	off_t frompos;
801 
802 	seensubj = seenfrom = NO;
803 	local = YES;
804 	subj[0] = from[0] = date[0] = 0;
805 
806 	/*
807 	 * Is this a normal message?
808 	 */
809 	if (fgets(inbuf, sizeof inbuf, infile)) {
810 		if (strncmp(inbuf, "From", 4)==0) {
811 			/*
812 			 * expected form starts with From
813 			 */
814 			seenfrom = YES;
815 			frompos = ftell(infile);
816 			ptr = from;
817 			in = nxtfld(inbuf);
818 			if (*in) while (*in && *in > ' ') {
819 				if (*in == ':' || *in == '@' || *in == '!')
820 					local = NO;
821 				*ptr++ = *in++;
822 				/* what about sizeof from ? */
823 			}
824 			*ptr = '\0';
825 			if (*(in = nxtfld(in)))
826 				strncpy(date, in, sizeof date);
827 			else {
828 				date[0] = '\n';
829 				date[1] = '\0';
830 			}
831 		}
832 		else {
833 			/*
834 			 * not the expected form
835 			 */
836 			fseek(infile, 0L, 0);
837 			return;
838 		}
839 	}
840 	else
841 		/*
842 		 * empty file ?
843 		 */
844 		return;
845 
846 	/*
847 	 * look for Subject line until EOF or a blank line
848 	 */
849 	while (fgets(inbuf, sizeof inbuf, infile)
850 	    && !(blankline = (inbuf[0] == '\n'))) {
851 		/*
852 		 * extract Subject line
853 		 */
854 		if (!seensubj && strncmp(inbuf, "Subj", 4)==0) {
855 			seensubj = YES;
856 			frompos = ftell(infile);
857 			strncpy(subj, nxtfld(inbuf), sizeof subj);
858 		}
859 	}
860 	if (!blankline)
861 		/*
862 		 * ran into EOF
863 		 */
864 		fseek(infile, frompos, 0);
865 
866 	if (!seensubj)
867 		/*
868 		 * for possible use with Mail
869 		 */
870 		strncpy(subj, "(No Subject)\n", sizeof subj);
871 }
872 
873 char *
874 nxtfld(s)
875 char *s;
876 {
877 	if (*s) while (*s && *s > ' ') s++;	/* skip over this field */
878 	if (*s) while (*s && *s <= ' ') s++;	/* find start of next field */
879 	return (s);
880 }
881