--- ../makefile.orig	2022-02-04 07:15:35.023914372 +0000
+++ ./makefile	2022-02-04 07:16:53.153727804 +0000
@@ -3,9 +3,9 @@
 #--------------------------------
 OBJ=.
 SRC=.
-CPPFLAGS:=$(shell dpkg-buildflags --get CPPFLAGS)
-CFLAGS:=$(shell dpkg-buildflags --get CFLAGS)
-LDFLAGS:=$(shell dpkg-buildflags --get LDFLAGS)
+CPPFLAGS?=$(shell dpkg-buildflags --get CPPFLAGS)
+CFLAGS?=$(shell dpkg-buildflags --get CFLAGS)
+LDFLAGS?=$(shell dpkg-buildflags --get LDFLAGS)
 
 all: jhead
 
@@ -22,4 +22,6 @@
 	rm -f $(objs) jhead
 
 install:
-	cp jhead ${DESTDIR}/usr/bin/
+	install -Dm700 jhead ${DESTDIR}$(PREFIX)/bin/
+	mkdir -p ${DESTDIR}$(PREFIX)/share/man/man1/
+	install -m600 jhead.1 ${DESTDIR}$(PREFIX)/share/man/man1/