diff -up asl-current/Makefile.destdir asl-current/Makefile
--- asl-current/Makefile.destdir	2018-03-28 15:09:51.000000000 -0600
+++ asl-current/Makefile	2018-03-30 11:51:33.385802518 -0600
@@ -3,6 +3,8 @@ include Makefile.def
 CURRDIR=./
 DATE=`date +"%d%m%Y"`
 
+DESTDIR=
+
 include makedefs.src
 
 include objdefs.unix
@@ -75,7 +77,7 @@ test: $(ALLTARGETS)
 	cd tests; ./testall "$(TESTDIRS)"
 
 install: $(ALLTARGETS)
-	PREFIX=$(PREFIX) ./install.sh $(BINDIR) $(INCDIR) $(MANDIR) $(LIBDIR) $(DOCDIR)
+	PREFIX=$(PREFIX) ./install.sh $(DESTDIR)$(BINDIR) $(DESTDIR)$(INCDIR) $(DESTDIR)$(MANDIR) $(DESTDIR)$(LIBDIR) $(DOCDIR)
 
 clean:
 	rm -f $(ALLTARGETS) $(RESCOMPTARGET) $(TEX2DOCTARGET) $(TEX2HTMLTARGET) *$(HOST_OBJEXTENSION) *$(TARG_OBJEXTENSION) *.p *.rsc tests/testlog testlog