Document the .Rv (return values) macro.

".Rv -std atexit" will generate the following text:

The atexit() function returns the value 0 if successful; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.

1 files changed, 19 insertions, 1 deletions

diff --git a/share/man/man7/mdoc.samples.7 b/share/man/man7/mdoc.samples.7
index 39e4c0b..f746482 100644
--- a/share/man/man7/mdoc.samples.7
+++ b/share/man/man7/mdoc.samples.7
@@ -30,7 +30,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     @(#)mdoc.samples.7	8.2 (Berkeley) 12/30/93
-.\"	$Id: mdoc.samples.7,v 1.12 1997/03/19 20:16:50 mpp Exp $
+.\"	$Id: mdoc.samples.7,v 1.13 1997/03/19 20:31:42 mpp Exp $
 .\"
 .\" This tutorial sampler invokes every macro in the package several
 .\" times and is guaranteed to give a worst case performance
@@ -147,6 +147,7 @@ outlined as follows:
 .It "Names" .
 .It "Options" .
 .It "Pathnames" .
+.It "Return Values"
 .It "Variables" .
 .It "Cross References" .
 .El
@@ -1301,6 +1302,23 @@ macro formats path or file names.
 The
 .Ql \&.Pa
 macro is parsed and is callable.
+.Ss Return Values
+The
+.Ql \&.Rv
+macro generates text for use in the
+.Sx RETURN VALUES
+section.
+.Pp
+.Dl Usage: .Rv [-std function]
+.Pp
+.Ql \&.Rv -std atexit
+will generate the following text:
+.Pp
+.Rv -std atexit
+.Pp
+The
+.Fl std
+option is valid only for manual page sections 2 and 3.
 .Ss Variables
 Generic variable reference:
 .Pp