use macro for /usr/local/plan9
diff --git a/man/man3/wctl.3 b/man/man3/wctl.3
index dfed6fc..9addaeb 100644
--- a/man/man3/wctl.3
+++ b/man/man3/wctl.3
@@ -34,6 +34,6 @@
 requests that the program's window be moved
 above all other windows and given the input focus.
 .SH SOURCE
-.B /usr/local/plan9/src/libdraw/x11-init.c
+.B \*9/src/libdraw/x11-init.c
 .br
-.B /usr/local/plan9/src/libdraw/x11-wsys.c
+.B \*9/src/libdraw/x11-wsys.c