Add the -m option to man's command line to augment the list of paths
searched by man. The string "OUT" must be substituted with chawan's $out
path after patching.
The required -m option is only available in the mandoc implementation.
--- a/adapter/protocol/man
+++ b/adapter/protocol/man
@@ -75,7 +75,7 @@ EOF
 
   $section =~ s:([^-\w\200-\377.,])::g;
   $man =~ s:([^-\w\200-\377.,])::g;
-  open(F, "GROFF_NO_SGR=1 MAN_KEEP_FORMATTING=1 $MAN $section $man 2> /dev/null |");
+  open(F, "GROFF_NO_SGR=1 MAN_KEEP_FORMATTING=1 $MAN -m OUT/share/man $section $man 2> /dev/null |");
 }
 
 $ok = 0;