Add the ability to display specific manual pages if passed on the

commandline. This mirrors the old (undocumented) GNU man functionality.
Also document this feature in the implementation notes section of
the manpage.

Submitted by:	arundel
Approved by:	wes (mentor implicit)

usr.bin/man/man.1

@@ -225,6 +225,13 @@ will search the following paths when considering section 4 manual pages in
 .It
 .Pa /usr/share/man/man4
 .El
+.Ss Displaying Specific Manual Files
+The
+.Nm
+utility also supports displaying a specific manual page if passed a path
+to the file as long as it contains a
+.Sq /
+character.
 .Sh ENVIRONMENT
 The following environment variables affect the execution of
 .Nm :

usr.bin/man/man.sh

@@ -356,6 +356,20 @@ man_display_page() {
 man_find_and_display() {
 	local found_page locpath p path sect
 
+	# Check to see if it's a file. But only if it has a '/' in
+	# the filename.
+	case "$1" in
+	*/*)	if [ -f "$1" -a -r "$1" ]; then
+			decho "Found a usable page, displaying that"
+			found_page=yes
+			unset use_cat
+			manpage="$1"
+			man_display_page
+			return
+		fi
+		;;
+	esac
+
 	IFS=:
 	for sect in $MANSECT; do
 		decho "Searching section $sect" 2