+$! Check for MMK/MMS
+$!
+$! This procedure accepts one parameter (contrib), which causes it to build
+$! the programs from the contrib directory instead of libpng.
+$!
+$ p1 = f$edit(p1,"UPCASE")
+$ if p1 .eqs. "CONTRIB"
+$ then
+$ set def [.contrib.gregbook]
+$ @makevms
+$ set def [-.pngminus]
+$ @makevms
+$ set def [--]
+$ exit
+$ endif
+$ Make = ""
+$ If F$Search ("Sys$System:MMS.EXE") .nes. "" Then Make = "MMS"
+$ If F$Type (MMK) .eqs. "STRING" Then Make = "MMK"
+$!