--- ./sys/unix/Makefile.doc.orig	2015-06-12 08:32:45.000000000 +0200
+++ ./sys/unix/Makefile.doc	2016-01-20 14:52:36.968982348 +0100
@@ -57,17 +57,17 @@
 	latex Guidebook.tex
 
 
-GAME	= nethack
-MANDIR	= /usr/man/man6
+GAME	= nethack%%HACKEXT%%
+MANDIR	= ${PREFIX}/share/man/man
 MANEXT	= 6
 
 # manual installation for most BSD-style systems
-GAMEMANCREATE = cat nethack.6 | $(NHGREP) >
-LEVMANCREATE = cat lev_comp.6 | $(NHGREP) >
-DGNMANCREATE = cat dgn_comp.6 | $(NHGREP) >
-RCVRMANCREATE = cat recover.6 | $(NHGREP) >
-DLBMANCREATE = cat dlb.6 | $(NHGREP) >
-MDMANCREATE = cat makedefs.6 | $(NHGREP) >
+GAMEMANCREATE = cat nethack.6 | $(NHGREP) > nethack.6.out ; ${BSD_INSTALL_MAN} nethack.6.out
+LEVMANCREATE = cat lev_comp.6 | $(NHGREP) > lev_comp.6.out ; ${BSD_INSTALL_MAN} lev_comp.6.out
+DGNMANCREATE = cat dgn_comp.6 | $(NHGREP) > dgn_comp.6.out ; ${BSD_INSTALL_MAN} dgn_comp.6.out
+RCVRMANCREATE = cat recover.6 | $(NHGREP) > recover.6.out ; ${BSD_INSTALL_MAN} recover.6.out
+DLBMANCREATE = cat dlb.6 | $(NHGREP) > dlb.6.out ; ${BSD_INSTALL_MAN} dlb.6.out
+MDMANCREATE = cat makedefs.6 | $(NHGREP) > makedefs.6.out ; ${BSD_INSTALL_MAN} makedefs.6.out
 # manual installation for most SYSV-style systems
 # GAMEMANCREATE = cat nethack.6 | $(NHGREP) | nroff -man - >
 # LEVMANCREATE = cat lev_comp.6 | $(NHGREP) | nroff -man - >
@@ -77,12 +77,12 @@
 # MDMANCREATE = cat makedefs.6 | $(NHGREP) | nroff -man - >
 
 manpages:
-	-$(GAMEMANCREATE) $(MANDIR)/$(GAME).$(MANEXT)
-	-$(LEVMANCREATE) $(MANDIR)/lev_comp.$(MANEXT)
-	-$(DGNMANCREATE) $(MANDIR)/dgn_comp.$(MANEXT)
-	-$(RCVRMANCREATE) $(MANDIR)/recover.$(MANEXT)
-	-$(DLBMANCREATE) $(MANDIR)/dlb.$(MANEXT)
-	-$(MDMANCREATE) $(MANDIR)/makedefs.$(MANEXT)
+	-$(GAMEMANCREATE) ${DESTDIR}$(MANDIR)$(MANEXT)/nethack%%HACKEXT%%.$(MANEXT)
+	-$(LEVMANCREATE) ${DESTDIR}$(MANDIR)$(MANEXT)/lev_comp%%HACKEXT%%.$(MANEXT)
+	-$(DGNMANCREATE) ${DESTDIR}$(MANDIR)$(MANEXT)/dgn_comp%%HACKEXT%%.$(MANEXT)
+	-$(RCVRMANCREATE) ${DESTDIR}$(MANDIR)$(MANEXT)/recover%%HACKEXT%%.$(MANEXT)
+	-$(DLBMANCREATE) ${DESTDIR}$(MANDIR)$(MANEXT)/dlb%%HACKEXT%%.$(MANEXT)
+	-$(MDMANCREATE) ${DESTDIR}$(MANDIR)$(MANEXT)/makedefs%%HACKEXT%%.$(MANEXT)
 
 # manual creation for distribution
 DISTRIB = Guidebook.txt nethack.txt lev_comp.txt dgn_comp.txt recover.txt \