Implement whatis(1) as a special apropos(1) mode as a part of

the mandoc(1) binary; not yet enabled for the general public.
Intended to replace src/usr.bin/whatis at a later time.
Coded by kristaps@, with a few tweaks by me.

To test this:
 $ mandocdb  # unless you have already done so earlier
 $ sudo ln -s /usr/bin/mandoc /usr/bin/whatis.m
 $ whatis.m mandoc apropos whatis
 $ whatis.m man

1 files changed, 13 insertions, 9 deletions

diff --git a/usr.bin/mandoc/apropos.c b/usr.bin/mandoc/apropos.c
index b1d84a42090..5e309236ca8 100644
--- a/usr.bin/mandoc/apropos.c
+++ b/usr.bin/mandoc/apropos.c
@@ -1,4 +1,4 @@
-/*	$Id: apropos.c,v 1.8 2011/11/26 16:41:35 schwarze Exp $ */
+/*	$Id: apropos.c,v 1.9 2011/11/28 00:16:38 schwarze Exp $ */
 /*
  * Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2011 Ingo Schwarze <schwarze@openbsd.org>
@@ -34,7 +34,7 @@ static	char	*progname;
 int
 apropos(int argc, char *argv[])
 {
-	int		 ch, rc;
+	int		 ch, rc, whatis;
 	struct manpaths	 paths;
 	size_t		 terms;
 	struct opts	 opts;
@@ -49,12 +49,13 @@ apropos(int argc, char *argv[])
 	else
 		++progname;
 
+	whatis = 0 == strncmp(progname, "whatis", 6);
+
 	memset(&paths, 0, sizeof(struct manpaths));
 	memset(&opts, 0, sizeof(struct opts));
 
 	auxpaths = defpaths = NULL;
 	e = NULL;
-	rc = 0;
 
 	while (-1 != (ch = getopt(argc, argv, "M:m:S:s:")))
 		switch (ch) {
@@ -72,20 +73,23 @@ apropos(int argc, char *argv[])
 			break;
 		default:
 			usage();
-			goto out;
+			return(EXIT_FAILURE);
 		}
 
 	argc -= optind;
 	argv += optind;
 
-	if (0 == argc) {
-		rc = 1;
-		goto out;
-	}
+	if (0 == argc) 
+		return(EXIT_SUCCESS);
+
+	rc = 0;
 
 	manpath_parse(&paths, defpaths, auxpaths);
 
-	if (NULL == (e = exprcomp(argc, argv, &terms))) {
+	e = whatis ? termcomp(argc, argv, &terms) :
+		     exprcomp(argc, argv, &terms);
+		
+	if (NULL == e) {
 		fprintf(stderr, "%s: Bad expression\n", progname);
 		goto out;
 	}