--- ./Makefile.in.orig	1993-02-24 14:36:56.000000000 +0100
+++ ./Makefile.in	2014-02-13 12:44:47.785972991 +0100
@@ -18,9 +18,9 @@
 default:        prog
 
 # Added the prefix macro, so that it was easier to change installation place.
-prefix        = /usr/local
-DEST          = $(prefix)/bin
-MANDEST       = $(prefix)/man/man1
+prefix        ?= $(PREFIX)
+DEST          = $(DESTDIR)$(prefix)/bin
+MANDEST       = $(DESTDIR)$(prefix)/man/man1
 SEC           = 1
 
 HDRS          = bitio.h\