--- Makefile	Sun Jan 23 14:01:55 2000
+++ Makefile.new	Mon May 29 23:12:10 2000
@@ -55,9 +55,9 @@
 ####################
 # C compiler options
 # GNU gcc is recommended.
-CC=gcc
+CC?=gcc
 # Use these with gcc
-CFLAGS=-g -Wall -W -fno-common -pedantic
+CFLAGS+= -Wall -W -fno-common -pedantic
 
 # If you don't have gcc, don't use -Wall -W -fno-common
 #CFLAGS=-g
@@ -81,13 +81,13 @@
 
 ## Installation prefix
 # Adjust to taste. Stuff gets installed here.
-PREFIX=/usr/local
+PREFIX?=/usr/local
 #PREFIX=/usr/local/X11
 
 ## X11 location and options
 # for X11R6
 # Point this at your X tree.
-XDIR=/usr/X11R6
+XDIR?=/usr/X11R6
 #XDIR=/usr/local/X11
 #XDIR=/usr/openwin