diff -uNr jhead-3.06.0.1/makefile jhead-3.06.0.1.mod/makefile
--- jhead-3.06.0.1/makefile	2021-04-14 13:02:45.000000000 +0100
+++ jhead-3.06.0.1.mod/makefile	2022-07-22 22:16:22.465375000 +0100
@@ -3,8 +3,8 @@
 #--------------------------------
 OBJ=obj
 SRC=.
-CFLAGS:=$(shell dpkg-buildflags --get CFLAGS)
-LDFLAGS:=$(shell dpkg-buildflags --get LDFLAGS)
+CFLAGS?=$(shell dpkg-buildflags --get CFLAGS)
+LDFLAGS?=$(shell dpkg-buildflags --get LDFLAGS)
 
 all: objdir jhead
 
@@ -24,5 +24,6 @@
 	rm -f $(objs) jhead
 
 install:
-	mkdir -p ${DESTDIR}/usr/bin/
-	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/