#! /bin/sh mkbin=/usr/local/plan9/bin/mk # check whether we are inside of a pf9 tree,# and try to guess a value for PF9 if pwd | grep sys/src > /dev/null; then 	base=`pwd | sed 's,/sys/src.*,,'` 	if test -f "$base/pf9.defaults"; then		user_objtype=$objtype		user_cputype=$cputype		user_sysname=$sysname 		. $base/pf9.defaults 		test -z "$user_objtype" || objtype=$user_objtype		test -z "$user_cputype" || cputype=$user_cputype		test -z "$user_sysname" || sysname=$user_sysname		PF9=$base				export \			PF9 \			cputype \			objtype \			sysname \ 		if test -f $PF9/$cputype/bin/mk; then			mkbin=$PF9/$cputype/bin/mk		fi	fifi  # try to make rc runableif test -z "$PLAN9"; then	PLAN9=$PF9/$cputype	export PLAN9elif test -d "$PLAN9"; then :else	PLAN9=$PF9/$cputype	export PLAN9fi exec $mkbin "$@"