--- ./Makefile.orig	2011-06-24 16:25:27.000000000 +0200
+++ ./Makefile	2012-09-17 13:38:44.926563330 +0200
@@ -16,14 +16,14 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
-prefix = /usr
+prefix = ${PREFIX}
 
-CC=gcc
+CC?=gcc
 
 VERSION=1.6.0
 TREE_DEST=tree
 BINDIR=${prefix}/bin
-MAN=tree.1
+MAN=doc/tree.1
 MANDIR=${prefix}/man/man1
 OBJS=tree.o unix.o html.o xml.o hash.o color.o
 
@@ -31,13 +31,13 @@
 
 # Linux defaults:
 #CFLAGS=-ggdb -Wall -DLINUX -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
-CFLAGS=-O4 -Wall  -DLINUX -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
-LDFLAGS=-s
+#CFLAGS=-O4 -Wall  -DLINUX -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
+#LDFLAGS=-s
 
 # Uncomment for FreeBSD:
-#CFLAGS=-O2 -Wall -fomit-frame-pointer
-#LDFLAGS=-s
-#OBJS+=strverscmp.o
+CFLAGS?=-O2 -Wall -fomit-frame-pointer
+LDFLAGS?=-s
+OBJS+=strverscmp.o
 
 # Uncomment for Solaris:
 #CC=cc
@@ -93,13 +93,11 @@
 	if [ -f tree.o ]; then rm *.o; fi
 	rm -f *~
 
-install: tree
-	install -d $(BINDIR)
-	install -d $(MANDIR)
-	if [ -e $(TREE_DEST) ]; then \
-		install -s $(TREE_DEST) $(BINDIR)/$(TREE_DEST); \
-	fi
-	install doc/$(MAN) $(MANDIR)/$(MAN)
+install: $(TREE_DEST)
+	@$(MKDIR) $(BINDIR)
+	@$(MKDIR) $(MANDIR)
+	${BSD_INSTALL_PROGRAM} $(TREE_DEST) $(BINDIR)
+	${BSD_INSTALL_MAN} $(MAN) $(MANDIR)
 
 distclean:
 	if [ -f tree.o ]; then rm *.o; fi