tmac/tmac.an: define .MR in a groff compatible way

groff 1.23.0 added .MR to its -man macro package.  The NEWS file states
that the inclusion of the macro "was prompted by its introduction to
Plan 9 from User Space's troff in August 2020."  From d32deab it seems
that the name for Plan 9 from User Space's implementation was suggested
by groff maintainer G. Brandon Robinson.

Not sure if the intention was to make these definitions compatible, but
it would be nice if they were.

Currently, Plan 9 from User Space's .MR expects its second argument to
be parenthesized.  groff's .MR does not.  This results in extra
parentheses appearing in manual references when viewing Plan 9 from User
Space's manual pages on a system using groff.

1 files changed, 14 insertions, 14 deletions

diff --git a/man/man3/acme.3 b/man/man3/acme.3
index 7c4ac67a..1535df04 100644
--- a/man/man3/acme.3
+++ b/man/man3/acme.3
@@ -141,7 +141,7 @@ char*	evsmprint(char *fmt, va_list arg)
 .SH DESCRIPTION
 .I Libacme
 provides a simple C interface for interacting with
-.MR acme (1)
+.MR acme 1
 windows.
 .PP
 A
@@ -168,7 +168,7 @@ Most of the library routines access files in the window's
 .I acme
 directory.
 See
-.MR acme (4)
+.MR acme 4
 for details.
 Many library routines take a format string
 .I fmt
@@ -179,11 +179,11 @@ denotes the result of formatting the string and arguments
 using
 .I smprint
 (see
-.MR print (3) ).
+.MR print 3 ).
 .PP
 .I Pipetowin
 runs the
-.MR rc (1)
+.MR rc 1
 command line
 .I fmt\fR, \fP...
 with 
@@ -199,7 +199,7 @@ Otherwise the command inherits the caller's standard error.
 .PP
 .I Pipewinto
 runs the 
-.MR rc (1)
+.MR rc 1
 command line
 .I fmt\fR, \fP...
 with the window's
@@ -300,7 +300,7 @@ to position
 relative to
 .I type
 (see
-.MR seek (3) ).
+.MR seek 3 ).
 .PP
 .I Winwrite
 writes the
@@ -317,7 +317,7 @@ The fields correspond to the fields in
 .IR acme 's
 event messages.
 See 
-.MR acme (4)
+.MR acme 4
 for detailed explanations.
 The fields are:
 .TP
@@ -384,7 +384,7 @@ that it should be handled internally.
 returns a pointer to a
 .B Channel
 (see
-.MR thread (3) )
+.MR thread 3 )
 on which event structures (not pointers) can be read.
 The first call to
 .I wineventchan
@@ -404,20 +404,20 @@ after calling
 and
 .I evsmprint
 are like
-.MR malloc (3) ,
+.MR malloc 3 ,
 .IR realloc ,
 .IR strdup
 (see
-.MR strcat (3) ),
+.MR strcat 3 ),
 and
 .IR vsmprint
 (see
-.MR print (3) ),
+.MR print 3 ),
 but they call
-.MR sysfatal (3)
+.MR sysfatal 3
 on error rather than returning nil.
 .SH SOURCE
 .B \*9/src/libacme
 .SH SEE ALSO
-.MR acme (1) ,
-.MR acme (4)
+.MR acme 1 ,
+.MR acme 4