xref: /original-bsd/usr.bin/msgs/msgs.c (revision 27393bdf)
1 /*-
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char copyright[] =
10 "@(#) Copyright (c) 1980, 1993\n\
11 	The Regents of the University of California.  All rights reserved.\n";
12 #endif /* not lint */
13 
14 #ifndef lint
15 static char sccsid[] = "@(#)msgs.c	8.2 (Berkeley) 04/28/95";
16 #endif /* not lint */
17 
18 /*
19  * msgs - a user bulletin board program
20  *
21  * usage:
22  *	msgs [fhlopq] [[-]number]	to read messages
23  *	msgs -s				to place messages
24  *	msgs -c [-days]			to clean up the bulletin board
25  *
26  * prompt commands are:
27  *	y	print message
28  *	n	flush message, go to next message
29  *	q	flush message, quit
30  *	p	print message, turn on 'pipe thru more' mode
31  *	P	print message, turn off 'pipe thru more' mode
32  *	-	reprint last message
33  *	s[-][<num>] [<filename>]	save message
34  *	m[-][<num>]	mail with message in temp mbox
35  *	x	exit without flushing this message
36  *	<num>	print message number <num>
37  */
38 
39 #define V7		/* will look for TERM in the environment */
40 #define OBJECT		/* will object to messages without Subjects */
41 /* #define REJECT	/* will reject messages without Subjects
42 			   (OBJECT must be defined also) */
43 /* #define UNBUFFERED	/* use unbuffered output */
44 
45 #include <sys/param.h>
46 #include <sys/dir.h>
47 #include <sys/ioctl.h>
48 #include <sys/stat.h>
49 #include <ctype.h>
50 #include <errno.h>
51 #include <pwd.h>
52 #include <setjmp.h>
53 #include <signal.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <termios.h>
58 #include <time.h>
59 #include <unistd.h>
60 #include "pathnames.h"
61 
62 #define CMODE	0666		/* bounds file creation mode */
63 #define NO	0
64 #define YES	1
65 #define SUPERUSER	0	/* superuser uid */
66 #define DAEMON		1	/* daemon uid */
67 #define NLINES	24		/* default number of lines/crt screen */
68 #define NDAYS	21		/* default keep time for messages */
69 #define DAYS	*24*60*60	/* seconds/day */
70 #define MSGSRC	".msgsrc"	/* user's rc file */
71 #define BOUNDS	"bounds"	/* message bounds file */
72 #define NEXT	"Next message? [yq]"
73 #define MORE	"More? [ynq]"
74 #define NOMORE	"(No more) [q] ?"
75 
76 typedef	char	bool;
77 
78 FILE	*msgsrc;
79 FILE	*newmsg;
80 char	*sep = "-";
81 char	inbuf[BUFSIZ];
82 char	fname[128];
83 char	cmdbuf[128];
84 char	subj[128];
85 char	from[128];
86 char	date[128];
87 char	*ptr;
88 char	*in;
89 bool	local;
90 bool	ruptible;
91 bool	totty;
92 bool	seenfrom;
93 bool	seensubj;
94 bool	blankline;
95 bool	printing = NO;
96 bool	mailing = NO;
97 bool	quitit = NO;
98 bool	sending = NO;
99 bool	intrpflg = NO;
100 int	uid;
101 int	msg;
102 int	prevmsg;
103 int	lct;
104 int	nlines;
105 int	Lpp = 0;
106 time_t	t;
107 time_t	keep;
108 
109 char	*mktemp();
110 char	*nxtfld();
111 void	onintr();
112 void	onsusp();
113 
114 /* option initialization */
115 bool	hdrs = NO;
116 bool	qopt = NO;
117 bool	hush = NO;
118 bool	send_msg = NO;
119 bool	locomode = NO;
120 bool	use_pager = NO;
121 bool	clean = NO;
122 bool	lastcmd = NO;
123 jmp_buf	tstpbuf;
124 
125 main(argc, argv)
126 int argc; char *argv[];
127 {
128 	bool newrc, already;
129 	int rcfirst = 0;		/* first message to print (from .rc) */
130 	int rcback = 0;			/* amount to back off of rcfirst */
131 	int firstmsg, nextmsg, lastmsg = 0;
132 	int blast = 0;
133 	FILE *bounds;
134 
135 #ifdef UNBUFFERED
136 	setbuf(stdout, NULL);
137 #endif
138 
139 	time(&t);
140 	setuid(uid = getuid());
141 	ruptible = (signal(SIGINT, SIG_IGN) == SIG_DFL);
142 	if (ruptible)
143 		signal(SIGINT, SIG_DFL);
144 
145 	argc--, argv++;
146 	while (argc > 0) {
147 		if (isdigit(argv[0][0])) {	/* starting message # */
148 			rcfirst = atoi(argv[0]);
149 		}
150 		else if (isdigit(argv[0][1])) {	/* backward offset */
151 			rcback = atoi( &( argv[0][1] ) );
152 		}
153 		else {
154 			ptr = *argv;
155 			while (*ptr) switch (*ptr++) {
156 
157 			case '-':
158 				break;
159 
160 			case 'c':
161 				if (uid != SUPERUSER && uid != DAEMON) {
162 					fprintf(stderr, "Sorry\n");
163 					exit(1);
164 				}
165 				clean = YES;
166 				break;
167 
168 			case 'f':		/* silently */
169 				hush = YES;
170 				break;
171 
172 			case 'h':		/* headers only */
173 				hdrs = YES;
174 				break;
175 
176 			case 'l':		/* local msgs only */
177 				locomode = YES;
178 				break;
179 
180 			case 'o':		/* option to save last message */
181 				lastcmd = YES;
182 				break;
183 
184 			case 'p':		/* pipe thru 'more' during long msgs */
185 				use_pager = YES;
186 				break;
187 
188 			case 'q':		/* query only */
189 				qopt = YES;
190 				break;
191 
192 			case 's':		/* sending TO msgs */
193 				send_msg = YES;
194 				break;
195 
196 			default:
197 				fprintf(stderr,
198 					"usage: msgs [fhlopq] [[-]number]\n");
199 				exit(1);
200 			}
201 		}
202 		argc--, argv++;
203 	}
204 
205 	/*
206 	 * determine current message bounds
207 	 */
208 	sprintf(fname, "%s/%s", _PATH_MSGS, BOUNDS);
209 	bounds = fopen(fname, "r");
210 
211 	if (bounds != NULL) {
212 		fscanf(bounds, "%d %d\n", &firstmsg, &lastmsg);
213 		fclose(bounds);
214 		blast = lastmsg;	/* save upper bound */
215 	}
216 
217 	if (clean)
218 		keep = t - (rcback? rcback : NDAYS) DAYS;
219 
220 	if (clean || bounds == NULL) {	/* relocate message bounds */
221 		struct direct *dp;
222 		struct stat stbuf;
223 		bool seenany = NO;
224 		DIR	*dirp;
225 
226 		dirp = opendir(_PATH_MSGS);
227 		if (dirp == NULL) {
228 			perror(_PATH_MSGS);
229 			exit(errno);
230 		}
231 
232 		firstmsg = 32767;
233 		lastmsg = 0;
234 
235 		for (dp = readdir(dirp); dp != NULL; dp = readdir(dirp)){
236 			register char *cp = dp->d_name;
237 			register int i = 0;
238 
239 			if (dp->d_ino == 0)
240 				continue;
241 			if (dp->d_namlen == 0)
242 				continue;
243 
244 			if (clean)
245 				sprintf(inbuf, "%s/%s", _PATH_MSGS, cp);
246 
247 			while (isdigit(*cp))
248 				i = i * 10 + *cp++ - '0';
249 			if (*cp)
250 				continue;	/* not a message! */
251 
252 			if (clean) {
253 				if (stat(inbuf, &stbuf) != 0)
254 					continue;
255 				if (stbuf.st_mtime < keep
256 				    && stbuf.st_mode&S_IWRITE) {
257 					unlink(inbuf);
258 					continue;
259 				}
260 			}
261 
262 			if (i > lastmsg)
263 				lastmsg = i;
264 			if (i < firstmsg)
265 				firstmsg = i;
266 			seenany = YES;
267 		}
268 		closedir(dirp);
269 
270 		if (!seenany) {
271 			if (blast != 0)	/* never lower the upper bound! */
272 				lastmsg = blast;
273 			firstmsg = lastmsg + 1;
274 		}
275 		else if (blast > lastmsg)
276 			lastmsg = blast;
277 
278 		if (!send_msg) {
279 			bounds = fopen(fname, "w");
280 			if (bounds == NULL) {
281 				perror(fname);
282 				exit(errno);
283 			}
284 			chmod(fname, CMODE);
285 			fprintf(bounds, "%d %d\n", firstmsg, lastmsg);
286 			fclose(bounds);
287 		}
288 	}
289 
290 	if (send_msg) {
291 		/*
292 		 * Send mode - place msgs in _PATH_MSGS
293 		 */
294 		bounds = fopen(fname, "w");
295 		if (bounds == NULL) {
296 			perror(fname);
297 			exit(errno);
298 		}
299 
300 		nextmsg = lastmsg + 1;
301 		sprintf(fname, "%s/%d", _PATH_MSGS, nextmsg);
302 		newmsg = fopen(fname, "w");
303 		if (newmsg == NULL) {
304 			perror(fname);
305 			exit(errno);
306 		}
307 		chmod(fname, 0644);
308 
309 		fprintf(bounds, "%d %d\n", firstmsg, nextmsg);
310 		fclose(bounds);
311 
312 		sending = YES;
313 		if (ruptible)
314 			signal(SIGINT, onintr);
315 
316 		if (isatty(fileno(stdin))) {
317 			ptr = getpwuid(uid)->pw_name;
318 			printf("Message %d:\nFrom %s %sSubject: ",
319 				nextmsg, ptr, ctime(&t));
320 			fflush(stdout);
321 			fgets(inbuf, sizeof inbuf, stdin);
322 			putchar('\n');
323 			fflush(stdout);
324 			fprintf(newmsg, "From %s %sSubject: %s\n",
325 				ptr, ctime(&t), inbuf);
326 			blankline = seensubj = YES;
327 		}
328 		else
329 			blankline = seensubj = NO;
330 		for (;;) {
331 			fgets(inbuf, sizeof inbuf, stdin);
332 			if (feof(stdin) || ferror(stdin))
333 				break;
334 			blankline = (blankline || (inbuf[0] == '\n'));
335 			seensubj = (seensubj || (!blankline && (strncmp(inbuf, "Subj", 4) == 0)));
336 			fputs(inbuf, newmsg);
337 		}
338 #ifdef OBJECT
339 		if (!seensubj) {
340 			printf("NOTICE: Messages should have a Subject field!\n");
341 #ifdef REJECT
342 			unlink(fname);
343 #endif
344 			exit(1);
345 		}
346 #endif
347 		exit(ferror(stdin));
348 	}
349 	if (clean)
350 		exit(0);
351 
352 	/*
353 	 * prepare to display messages
354 	 */
355 	totty = (isatty(fileno(stdout)) != 0);
356 	use_pager = use_pager && totty;
357 
358 	sprintf(fname, "%s/%s", getenv("HOME"), MSGSRC);
359 	msgsrc = fopen(fname, "r");
360 	if (msgsrc) {
361 		newrc = NO;
362 		fscanf(msgsrc, "%d\n", &nextmsg);
363 		fclose(msgsrc);
364 		if (nextmsg > lastmsg+1) {
365 			printf("Warning: bounds have been reset (%d, %d)\n",
366 				firstmsg, lastmsg);
367 			truncate(fname, (off_t)0);
368 			newrc = YES;
369 		}
370 		else if (!rcfirst)
371 			rcfirst = nextmsg - rcback;
372 	}
373 	else
374 		newrc = YES;
375 	msgsrc = fopen(fname, "r+");
376 	if (msgsrc == NULL)
377 		msgsrc = fopen(fname, "w");
378 	if (msgsrc == NULL) {
379 		perror(fname);
380 		exit(errno);
381 	}
382 	if (rcfirst) {
383 		if (rcfirst > lastmsg+1) {
384 			printf("Warning: the last message is number %d.\n",
385 				lastmsg);
386 			rcfirst = nextmsg;
387 		}
388 		if (rcfirst > firstmsg)
389 			firstmsg = rcfirst;	/* don't set below first msg */
390 	}
391 	if (newrc) {
392 		nextmsg = firstmsg;
393 		fseek(msgsrc, 0L, 0);
394 		fprintf(msgsrc, "%d\n", nextmsg);
395 		fflush(msgsrc);
396 	}
397 
398 #ifdef V7
399 	if (totty) {
400 		struct winsize win;
401 		if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1)
402 			Lpp = win.ws_row;
403 		if (Lpp <= 0) {
404 			if (tgetent(inbuf, getenv("TERM")) <= 0
405 			    || (Lpp = tgetnum("li")) <= 0) {
406 				Lpp = NLINES;
407 			}
408 		}
409 	}
410 #endif
411 	Lpp -= 6;	/* for headers, etc. */
412 
413 	already = NO;
414 	prevmsg = firstmsg;
415 	printing = YES;
416 	if (ruptible)
417 		signal(SIGINT, onintr);
418 
419 	/*
420 	 * Main program loop
421 	 */
422 	for (msg = firstmsg; msg <= lastmsg; msg++) {
423 
424 		sprintf(fname, "%s/%d", _PATH_MSGS, msg);
425 		newmsg = fopen(fname, "r");
426 		if (newmsg == NULL)
427 			continue;
428 
429 		gfrsub(newmsg);		/* get From and Subject fields */
430 		if (locomode && !local) {
431 			fclose(newmsg);
432 			continue;
433 		}
434 
435 		if (qopt) {	/* This has to be located here */
436 			printf("There are new messages.\n");
437 			exit(0);
438 		}
439 
440 		if (already && !hdrs)
441 			putchar('\n');
442 
443 		/*
444 		 * Print header
445 		 */
446 		if (totty)
447 			signal(SIGTSTP, onsusp);
448 		(void) setjmp(tstpbuf);
449 		already = YES;
450 		nlines = 2;
451 		if (seenfrom) {
452 			printf("Message %d:\nFrom %s %s", msg, from, date);
453 			nlines++;
454 		}
455 		if (seensubj) {
456 			printf("Subject: %s", subj);
457 			nlines++;
458 		}
459 		else {
460 			if (seenfrom) {
461 				putchar('\n');
462 				nlines++;
463 			}
464 			while (nlines < 6
465 			    && fgets(inbuf, sizeof inbuf, newmsg)
466 			    && inbuf[0] != '\n') {
467 				fputs(inbuf, stdout);
468 				nlines++;
469 			}
470 		}
471 
472 		lct = linecnt(newmsg);
473 		if (lct)
474 			printf("(%d%slines) ", lct, seensubj? " " : " more ");
475 
476 		if (hdrs) {
477 			printf("\n-----\n");
478 			fclose(newmsg);
479 			continue;
480 		}
481 
482 		/*
483 		 * Ask user for command
484 		 */
485 		if (totty)
486 			ask(lct? MORE : (msg==lastmsg? NOMORE : NEXT));
487 		else
488 			inbuf[0] = 'y';
489 		if (totty)
490 			signal(SIGTSTP, SIG_DFL);
491 cmnd:
492 		in = inbuf;
493 		switch (*in) {
494 			case 'x':
495 			case 'X':
496 				exit(0);
497 
498 			case 'q':
499 			case 'Q':
500 				quitit = YES;
501 				printf("--Postponed--\n");
502 				exit(0);
503 				/* intentional fall-thru */
504 			case 'n':
505 			case 'N':
506 				if (msg >= nextmsg) sep = "Flushed";
507 				prevmsg = msg;
508 				break;
509 
510 			case 'p':
511 			case 'P':
512 				use_pager = (*in++ == 'p');
513 				/* intentional fallthru */
514 			case '\n':
515 			case 'y':
516 			default:
517 				if (*in == '-') {
518 					msg = prevmsg-1;
519 					sep = "replay";
520 					break;
521 				}
522 				if (isdigit(*in)) {
523 					msg = next(in);
524 					sep = in;
525 					break;
526 				}
527 
528 				prmesg(nlines + lct + (seensubj? 1 : 0));
529 				prevmsg = msg;
530 
531 		}
532 
533 		printf("--%s--\n", sep);
534 		sep = "-";
535 		if (msg >= nextmsg) {
536 			nextmsg = msg + 1;
537 			fseek(msgsrc, 0L, 0);
538 			fprintf(msgsrc, "%d\n", nextmsg);
539 			fflush(msgsrc);
540 		}
541 		if (newmsg)
542 			fclose(newmsg);
543 		if (quitit)
544 			break;
545 	}
546 
547 	/*
548 	 * Make sure .rc file gets updated
549 	 */
550 	if (--msg >= nextmsg) {
551 		nextmsg = msg + 1;
552 		fseek(msgsrc, 0L, 0);
553 		fprintf(msgsrc, "%d\n", nextmsg);
554 		fflush(msgsrc);
555 	}
556 	if (already && !quitit && lastcmd && totty) {
557 		/*
558 		 * save or reply to last message?
559 		 */
560 		msg = prevmsg;
561 		ask(NOMORE);
562 		if (inbuf[0] == '-' || isdigit(inbuf[0]))
563 			goto cmnd;
564 	}
565 	if (!(already || hush || qopt))
566 		printf("No new messages.\n");
567 	exit(0);
568 }
569 
570 prmesg(length)
571 int length;
572 {
573 	FILE *outf;
574 
575 	if (use_pager && length > Lpp) {
576 		signal(SIGPIPE, SIG_IGN);
577 		signal(SIGQUIT, SIG_IGN);
578 		sprintf(cmdbuf, _PATH_PAGER, Lpp);
579 		outf = popen(cmdbuf, "w");
580 		if (!outf)
581 			outf = stdout;
582 		else
583 			setbuf(outf, (char *)NULL);
584 	}
585 	else
586 		outf = stdout;
587 
588 	if (seensubj)
589 		putc('\n', outf);
590 
591 	while (fgets(inbuf, sizeof inbuf, newmsg)) {
592 		fputs(inbuf, outf);
593 		if (ferror(outf)) {
594 			clearerr(outf);
595 			break;
596 		}
597 	}
598 
599 	if (outf != stdout) {
600 		pclose(outf);
601 		signal(SIGPIPE, SIG_DFL);
602 		signal(SIGQUIT, SIG_DFL);
603 	}
604 	else {
605 		fflush(stdout);
606 	}
607 
608 	/* trick to force wait on output */
609 	tcdrain(fileno(stdout));
610 }
611 
612 void
613 onintr()
614 {
615 	signal(SIGINT, onintr);
616 	if (mailing)
617 		unlink(fname);
618 	if (sending) {
619 		unlink(fname);
620 		puts("--Killed--");
621 		exit(1);
622 	}
623 	if (printing) {
624 		putchar('\n');
625 		if (hdrs)
626 			exit(0);
627 		sep = "Interrupt";
628 		if (newmsg)
629 			fseek(newmsg, 0L, 2);
630 		intrpflg = YES;
631 	}
632 }
633 
634 /*
635  * We have just gotten a susp.  Suspend and prepare to resume.
636  */
637 void
638 onsusp()
639 {
640 
641 	signal(SIGTSTP, SIG_DFL);
642 	sigsetmask(0);
643 	kill(0, SIGTSTP);
644 	signal(SIGTSTP, onsusp);
645 	if (!mailing)
646 		longjmp(tstpbuf, 0);
647 }
648 
649 linecnt(f)
650 FILE *f;
651 {
652 	off_t oldpos = ftell(f);
653 	int l = 0;
654 	char lbuf[BUFSIZ];
655 
656 	while (fgets(lbuf, sizeof lbuf, f))
657 		l++;
658 	clearerr(f);
659 	fseek(f, oldpos, 0);
660 	return (l);
661 }
662 
663 next(buf)
664 char *buf;
665 {
666 	int i;
667 	sscanf(buf, "%d", &i);
668 	sprintf(buf, "Goto %d", i);
669 	return(--i);
670 }
671 
672 ask(prompt)
673 char *prompt;
674 {
675 	char	inch;
676 	int	n, cmsg;
677 	off_t	oldpos;
678 	FILE	*cpfrom, *cpto;
679 
680 	printf("%s ", prompt);
681 	fflush(stdout);
682 	intrpflg = NO;
683 	(void) fgets(inbuf, sizeof inbuf, stdin);
684 	if ((n = strlen(inbuf)) > 0 && inbuf[n - 1] == '\n')
685 		inbuf[n - 1] = '\0';
686 	if (intrpflg)
687 		inbuf[0] = 'x';
688 
689 	/*
690 	 * Handle 'mail' and 'save' here.
691 	 */
692 	if ((inch = inbuf[0]) == 's' || inch == 'm') {
693 		if (inbuf[1] == '-')
694 			cmsg = prevmsg;
695 		else if (isdigit(inbuf[1]))
696 			cmsg = atoi(&inbuf[1]);
697 		else
698 			cmsg = msg;
699 		sprintf(fname, "%s/%d", _PATH_MSGS, cmsg);
700 
701 		oldpos = ftell(newmsg);
702 
703 		cpfrom = fopen(fname, "r");
704 		if (!cpfrom) {
705 			printf("Message %d not found\n", cmsg);
706 			ask (prompt);
707 			return;
708 		}
709 
710 		if (inch == 's') {
711 			in = nxtfld(inbuf);
712 			if (*in) {
713 				for (n=0; in[n] > ' '; n++) { /* sizeof fname? */
714 					fname[n] = in[n];
715 				}
716 				fname[n] = NULL;
717 			}
718 			else
719 				strcpy(fname, "Messages");
720 		}
721 		else {
722 			strcpy(fname, _PATH_TMP);
723 			mktemp(fname);
724 			sprintf(cmdbuf, _PATH_MAIL, fname);
725 			mailing = YES;
726 		}
727 		cpto = fopen(fname, "a");
728 		if (!cpto) {
729 			perror(fname);
730 			mailing = NO;
731 			fseek(newmsg, oldpos, 0);
732 			ask(prompt);
733 			return;
734 		}
735 
736 		while (n = fread(inbuf, 1, sizeof inbuf, cpfrom))
737 			fwrite(inbuf, 1, n, cpto);
738 
739 		fclose(cpfrom);
740 		fclose(cpto);
741 		fseek(newmsg, oldpos, 0);	/* reposition current message */
742 		if (inch == 's')
743 			printf("Message %d saved in \"%s\"\n", cmsg, fname);
744 		else {
745 			system(cmdbuf);
746 			unlink(fname);
747 			mailing = NO;
748 		}
749 		ask(prompt);
750 	}
751 }
752 
753 gfrsub(infile)
754 FILE *infile;
755 {
756 	off_t frompos;
757 
758 	seensubj = seenfrom = NO;
759 	local = YES;
760 	subj[0] = from[0] = date[0] = NULL;
761 
762 	/*
763 	 * Is this a normal message?
764 	 */
765 	if (fgets(inbuf, sizeof inbuf, infile)) {
766 		if (strncmp(inbuf, "From", 4)==0) {
767 			/*
768 			 * expected form starts with From
769 			 */
770 			seenfrom = YES;
771 			frompos = ftell(infile);
772 			ptr = from;
773 			in = nxtfld(inbuf);
774 			if (*in) while (*in && *in > ' ') {
775 				if (*in == ':' || *in == '@' || *in == '!')
776 					local = NO;
777 				*ptr++ = *in++;
778 				/* what about sizeof from ? */
779 			}
780 			*ptr = NULL;
781 			if (*(in = nxtfld(in)))
782 				strncpy(date, in, sizeof date);
783 			else {
784 				date[0] = '\n';
785 				date[1] = NULL;
786 			}
787 		}
788 		else {
789 			/*
790 			 * not the expected form
791 			 */
792 			fseek(infile, 0L, 0);
793 			return;
794 		}
795 	}
796 	else
797 		/*
798 		 * empty file ?
799 		 */
800 		return;
801 
802 	/*
803 	 * look for Subject line until EOF or a blank line
804 	 */
805 	while (fgets(inbuf, sizeof inbuf, infile)
806 	    && !(blankline = (inbuf[0] == '\n'))) {
807 		/*
808 		 * extract Subject line
809 		 */
810 		if (!seensubj && strncmp(inbuf, "Subj", 4)==0) {
811 			seensubj = YES;
812 			frompos = ftell(infile);
813 			strncpy(subj, nxtfld(inbuf), sizeof subj);
814 		}
815 	}
816 	if (!blankline)
817 		/*
818 		 * ran into EOF
819 		 */
820 		fseek(infile, frompos, 0);
821 
822 	if (!seensubj)
823 		/*
824 		 * for possible use with Mail
825 		 */
826 		strncpy(subj, "(No Subject)\n", sizeof subj);
827 }
828 
829 char *
830 nxtfld(s)
831 char *s;
832 {
833 	if (*s) while (*s && *s > ' ') s++;	/* skip over this field */
834 	if (*s) while (*s && *s <= ' ') s++;	/* find start of next field */
835 	return (s);
836 }
837