patch-Makefile

--- Makefile.orig	2017-09-11 13:43:01 UTC
+++ Makefile
@@ -22,14 +22,20 @@
 # THIS SOFTWARE.
 # ****************************************************************/
 
-CFLAGS = -g -Wall -O2
+CFLAGS ?= -g -Wall -O2
 
-CC = gcc
+CC ?= gcc
 
-YACC = bison -y
+# YACC = bison -y
 YACC = yacc
 YFLAGS = -d
 
+MKDIR	?= mkdir
+INSTALL	?= install
+DESTDIR	?= .
+PREFIX	?= /usr/local
+STRIP	?= strip
+
 OFILES = b.o main.o parse.o proctab.o tran.o lib.o run.o lex.o addon.o
 
 SOURCE = awk.h ytab.c ytab.h proto.h awkgram.y lex.c b.c main.c \
@@ -61,5 +67,15 @@ maketab:	ytab.h maketab.c
 names:
 	@echo $(LISTING)
 
+.PHONY:	intall-strip install clean
+
+install-strip: install
+	${STRIP} ${DESTDIR}${PREFIX}/bin/bioawk
+
+install:
+	${MKDIR} -p ${DESTDIR}${PREFIX}/bin
+	${INSTALL} -c bioawk ${DESTDIR}${PREFIX}/bin
+
 clean:
-	rm -fr a.out *.o *.obj maketab maketab.exe *.bb *.bbg *.da *.gcov *.gcno *.gcda awk bioawk ytab.* proctab.c *.dSYM
+	rm -fr a.out *.o *.obj maketab maketab.exe *.bb *.bbg *.da *.gcov \
+		*.gcno *.gcda awk bioawk ytab.* proctab.c *.dSYM