New features:

=============
1. Add -b option to make a backup package of the installed port
2. Add -g option to make a package of the new port
3. Add -o option to replace an installed port with a new port from a
different location (e.g., portmaster -o emulators/linux_base-fc4 linux_base)
The second argument can also be specified as the name of the installed port
(e.g., linux_base-8-8.0_15)
4. Add -s option to detect no-longer-needed dependencies, and offer the user
a choice to delete them.

General improvements:
=====================
1. Update usage() to reflect reality, and organize it better
2. Switch to using DEPORIGIN to detect missing dependency tracking, which
provides dramatically fewer false positives, and more useful tools to fix
actual problems
3. Factor out more common code into functions
4. Only pay attention to +REQUIRED_BY files for dependency tracking if they
are > 0 bytes
5. Simplify option parsing
6. Make whitespace more consistent in -a message
7. Only grep for dependencies if we're upgrading an installed port
8. If using -o, or a port moved, try to find the names of the old distfiles,
and offer the user the choice to remove all of the, or prune the stale ones.

Bug fixes:
==========
1. Fix the PATH if a user is using ccache
2. Handle the case where there is no ORIGIN in a +CONTENTS file
3. Ignore errors in the tail of fetchlog, since if the file is gone we'll
exit the loop anyway

2 files changed, 223 insertions, 62 deletions

diff --git a/ports-mgmt/portmaster/files/portmaster.8 b/ports-mgmt/portmaster/files/portmaster.8
index b1144a9fcf8f..cd5424035525 100644
--- a/ports-mgmt/portmaster/files/portmaster.8
+++ b/ports-mgmt/portmaster/files/portmaster.8
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd May 19, 2006
+.Dd June 19, 2006
 .Dt PORTMASTER 8
 .Os
 .Sh NAME
@@ -32,24 +32,31 @@
 .Nd manage your ports
 .Sh SYNOPSIS
 .Nm
-.Op Fl CGanv [uf|i] [D|d] m Ar arguments for make
+.Op Fl CGbgnv [uf|i] [D|d] m Ar arguments for make
 .Op Ar name of port directory in /var/db/pkg
-.Pp
-.Op Fl CGanv [uf|i] [D|d] m Ar arguments for make
+.Nm
+.Op Fl CGbgnv [uf|i] [D|d] m Ar arguments for make
 .Op Ar glob pattern from /var/db/pkg
-.Pp
-.Op Fl CGanv [uf|i] [D|d] m Ar arguments for make
+.Nm
+.Op Fl CGbgnv [uf|i] [D|d] m Ar arguments for make
 .Op Fl p Ar port directory in /usr/ports
-.Pp
-.Op Fl CGanv [uf|i] [D|d] m Ar arguments for make
+.Nm
+.Op Fl CGbgnv [uf|i] [D|d] m Ar arguments for make
 .Op Ar full path to /usr/ports/foo/bar
-.Pp
-.Op Fl CGnv [uf|i] [D|d] m Ar arguments for make
+.Nm
+.Op Fl CGbgnv [uf|i] [D|d] m Ar arguments for make
+.Op Fl o Ar <new port dir in /usr/ports> <installed port>
+.Nm
+.Op Fl CGbgnv [uf|i] [D|d] m Ar arguments for make
 .Op Fl r Ar name/glob of port in /var/db/pkg
-.Pp
-.Op Fl h
-.Pp
+.Nm
+.Op Fl a CGbgnv [uf|i] [D|d] m Ar arguments for make
+.Nm
 .Op Fl l
+.Nm
+.Op Fl s
+.Nm
+.Op Fl h
 .Pp
 .Sh DESCRIPTION
 The
@@ -85,36 +92,46 @@ or start downloading the new ones.
 The options are as follows:
 .Bl -tag -width F1
 .It Fl C
-Prevents 'make clean' being run in port directory
+prevents 'make clean' being run in port directory
 .It Fl G
-Prevents the recursive 'make config'
+prevents the recursive 'make config'
 .It Fl a
 check all ports, update as necessary
+.It Fl b
+create a backup package of the installed port (if any)
+.It Fl g
+create a package of the new port
 .It Fl n
 do not actually perform any updates
 .It Fl v
 verbose output
+.It Fl u
+unattended mode, accepts defaults for all portmaster dialogues
 .It Fl f
 always rebuild ports (overrides -i)
 .It Fl i
 interactive update mode
-.It Fl u
-unattended mode, accepts defaults for all portmaster dialogues
 .It Fl D
 prevents cleaning of distfiles
 .It Fl d
 always clean distfiles
-.It Fl p Ar port directory in /usr/ports
-Specify the full path to a port directory
 .It Fl m Ar arguments for make
 any arguments to supply to
 .Xr make 1
+.It Fl p Ar port directory in /usr/ports
+Specify the full path to a port directory
+.It Fl o Ar <new port dir in /usr/ports> <installed port>
+Replace the installed port with a port from a different origin
 .It Fl r Ar name/glob of port in /var/db/pkg
 rebuild port, and all ports that depend on it
-.It Fl h
-display help file
+.It Fl a
+check all ports, update as necessary
 .It Fl l
 list all installed ports by category
+.It Fl s
+clean out stale ports that used to be depended on
+.It Fl h
+display help file
 .El
 .Sh FILES
 .Bl -tag -width ".Pa $HOME/.portmasterrc" -compact
@@ -137,6 +154,7 @@ command:
 .Dl "portmaster -p /usr/ports/foo/fooport"
 .Dl "portmaster foo/fooport"
 .Dl "portmaster -r fooport-1.23"
+.Dl "portmaster -o emulators/linux_base-fc4 linux_base-8-8.0_15"
 .Sh SEE ALSO
 .Xr make 1
 .Xr ports 7
diff --git a/ports-mgmt/portmaster/files/portmaster.sh.in b/ports-mgmt/portmaster/files/portmaster.sh.in
index 4fb6f3908681..ddaa26305d04 100644
--- a/ports-mgmt/portmaster/files/portmaster.sh.in
+++ b/ports-mgmt/portmaster/files/portmaster.sh.in
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-# Local version: 1.65
+# Local version: 1.77
 # $FreeBSD$
 
 # Copyright (c) 2005-2006 Douglas Barton, All rights reserved
@@ -8,7 +8,13 @@
 
 # %%LOCALBASE%% and %%X11BASE%% are needed in path for make
 PATH=/bin:/usr/bin:/sbin:/usr/sbin:%%LOCALBASE%%/bin:%%X11BASE%%/bin
+if [ -n "$CCACHE_PATH" ]; then
+	if [ -z "$NOCCACHE" ]; then
+		PATH="%%LOCALBASE%%/libexec/ccache:$PATH"
+	fi
+fi
 export PATH
+
 umask 022
 
 usage () {
@@ -16,28 +22,39 @@ usage () {
 	echo "portmaster version $VERSION_NUMBER"
 	echo ''
 	echo 'Usage:'
-	echo "${0##*/} [-CGanv uf|i D|d] <full name of port directory in $pdb>"
-	echo "${0##*/} [-CGanv uf|i D|d] <glob pattern of directory in $pdb>"
-	echo "${0##*/} [-CGanv uf|i D|d] -p <port directory in $pd>"
-	echo "${0##*/} [-CGanv uf|i D|d] <full path to $pd/foo/bar>"
-	echo "${0##*/} [-CGnv uf|i D|d] -r <name/glob of port directory in $pdb>"
-	echo "${0##*/} -h"
+	echo "Common flags: [-CGbgnv uf|i D|d] [-m <arguments for make>]"
+	echo "${0##*/} [Common flags] <full name of port directory in $pdb>"
+	echo "${0##*/} [Common flags] <glob pattern of directory in $pdb>"
+	echo "${0##*/} [Common flags] -p <port directory in $pd>"
+	echo "${0##*/} [Common flags] <full path to $pd/foo/bar>"
+	echo "${0##*/} [Common flags] -o <new port dir in $pd> <installed port>"
+	echo "${0##*/} [Common flags] -r <name/glob of port directory in $pdb>"
+	echo "${0##*/} -a [Common flags]"
 	echo "${0##*/} -l"
+	echo "${0##*/} -s"
+	echo "${0##*/} -h"
 	echo ''
 	echo "-C prevents 'make clean' being run in port directory"
 	echo "-G prevents recursive 'make config'"
-	echo '-a check all ports, update as necessary'
-	echo '-n do not launch child process to update dependencies'
+	echo '-b create a backup package of the installed port (if any)'
+	echo '-g create a package of the new port'
+	echo '-n do not actually make or install any ports'
 	echo '-v verbose output'
+	echo "-u unattended mode -- accept defaults for all but 'make config'"
 	echo '-f always rebuild ports (overrides -i)'
 	echo '-i interactive update mode'
 	echo '-D prevents cleaning of distfiles'
 	echo '-d always clean distfiles'
 	echo "-m <arguments for the 'make' command line>"
+	echo ''
+	echo '-o Replace the installed port with a port from a different origin'
 	echo '-r rebuild port, and all ports that depend on it'
-	echo "-u unattended mode -- accept defaults for all but 'make config'"
-	echo '-h display this help file'
+	echo '-a check all ports, update as necessary'
+	echo ''
 	echo '-l list installed ports by category'
+	echo '-s clean out stale ports that used to be depended on'
+	echo ''
+	echo '-h display this help file'
 	echo ''
 	exit 1
 }
@@ -80,9 +97,9 @@ dep_warn () {
 	echo ''
 	echo "===>>> Warning! Potential unrecorded dependencies on $new_port"
 	echo "===>>> From existing +CONTENTS files:"
-	grep "pkgdep ${short_port}-" $pdb/*/+CONTENTS |
-	    sort -u | sed "s#$pdb/##"
-	num_ports1=`grep "pkgdep ${short_port}-" $pdb/*/+CONTENTS |
+	grep -B1 DEPORIGIN:$upg_origin$ $pdb/*/+CONTENTS |
+	    sort -u | sed -e "s#$pdb/##" -e 1d
+	num_ports1=`grep DEPORIGIN:$upg_origin$ $pdb/*/+CONTENTS |
 	    sort -u | wc -l | awk '{print $1}'`
 	echo "===>>> $num_ports1 ports"
 	echo ''
@@ -161,10 +178,31 @@ check_interactive () {
 	return 0
 }
 
+iport_from_origin () {
+	local dir
+
+	dir=`grep -l "@comment ORIGIN:${1}$" $pdb/*/+CONTENTS`
+	dir="${dir%/+CONTENTS}"
+	dir="${dir#$pdb/}"
+
+	echo $dir
+}
+
+origin_from_pdb () {
+	grep '@comment ORIGIN' ${1}/+CONTENTS | cut -f2 -d':'
+}
+
 check_for_updates () {
 	local upd_port port_ver do_update
 
-	upd_port=`grep ' ORIGIN' $pdb/$1/+CONTENTS | cut -f2 -d':'`
+	upd_port=`origin_from_pdb $pdb/$1`
+	if [ -z "$upd_port" ]; then
+		if [ -n "$VERBOSE" ]; then
+			echo "===>>> No ORIGIN in $pdb/$1/+CONTENTS"
+			echo ''
+		fi
+		return 0
+	fi
 
 	if [ -d "$pd/$upd_port" ]; then
 		cd $pd/$upd_port ||
@@ -240,7 +278,7 @@ ports_by_category () {
 		# Handle regular files, such as portupgrade's pkgdb.db
 		test -d "$pkg" || continue
 
-		if [ -e "$pkg/+REQUIRED_BY" ]; then
+		if [ -s "$pkg/+REQUIRED_BY" ]; then
 			if grep '^@pkgdep ' $pkg/+CONTENTS >/dev/null; then
 				branches="$branches $pkg"
 			else
@@ -291,10 +329,8 @@ dependency_check () {
 			fi
 		fi
 
-		cur_p=`grep -l " ORIGIN:${dep_port#$pd/}$" $pdb/*/+CONTENTS`
+		cur_p=`iport_from_origin ${dep_port#$pd/}`
 		if [ -n "$cur_p" ]; then
-			cur_p=${cur_p%/+CONTENTS}
-			cur_p=${cur_p##*/}
 			upd_args=$cur_p
 		else
 			upd_args="-p $dep_port"		# Sensible default
@@ -306,10 +342,8 @@ dependency_check () {
 			op=`echo $op | sed 's/.* //'`
 
 			if [ -n "$op" ]; then
-				old_p=`grep -l " ORIGIN:${op}$" $pdb/*/+CONTENTS`
+				old_p=`iport_from_origin ${op}`
 				if [ -n "$old_p" ]; then
-					old_p=${old_p%/+CONTENTS}
-					old_p=${old_p##*/}
 					upd_args=$old_p
 				fi
 			fi
@@ -378,29 +412,34 @@ fi
 : ${pdb:=/var/db/pkg}
 
 # Save switches for potential child processes
-while getopts 'CDGadfhilm:np:r:uv' COMMAND_LINE_ARGUMENT ; do
+while getopts 'CDGabdfghilm:nop:r:suv' COMMAND_LINE_ARGUMENT ; do
 	case "${COMMAND_LINE_ARGUMENT}" in
 	C)	DONT_PRE_CLEAN=yes; ARGS="-C $ARGS" ;;
 	D)	DONT_SCRUB_DISTFILES=yes; ARGS="-D $ARGS" ;;
 	G)	NO_RECURSIVE_CONFIG=yes; ARGS="-G $ARGS" ;;
 	a)	UPDATE_ALL=yes ;;
+	b)	BACKUP=yes; ARGS="-b $ARGS" ;;
 	d)	ALWAYS_SCRUB_DISTFILES=yes; ARGS="-d $ARGS" ;;
 	f)	FORCE_PARENT=yes
 		FORCE=yes
 		UPDATES_DONE_LIST=`mktemp -t updates_done_list`
 		export FORCE UPDATES_DONE_LIST
 		;;
+	g)	MAKE_PACKAGE=yes; ARGS="-g $ARGS" ;;
 	h)	usage ; exit 0 ;;
 	i)	INTERACTIVE_UPDATE=yes; ARGS="-i $ARGS" ;;
 	l)	LIST=yes ;;
 	m)	MAKE_ARGS=$OPTARG; ARGS="-m $MAKE_ARGS $ARGS" ;;
 	n)	NO_ACTION=yes ;;
+	o)	REPLACE_ORIGIN=yes ;;
 	p)	portdir="${OPTARG#$pd/}" ;;
 	r)	UPDATE_REQ_BYS=yes; upg_port=$OPTARG ;;
+	s)	CLEAN_STALE=yes ;;
 	u)	UNATTENDED=yes; ARGS="-u $ARGS" ;;
 	v)	VERBOSE=yes; ARGS="-v $ARGS" ;;
 	esac
 done
+shift $(( $OPTIND - 1 ))
 
 if [ -n "$LIST" ]; then
 	ports_by_category
@@ -443,6 +482,28 @@ if [ -n "$LIST" ]; then
 	exit 0
 fi
 
+if [ -n "$CLEAN_STALE" ]; then
+	for file in `find $pdb/ -name \+REQUIRED_BY -empty` ; do
+		dir="${file%/+REQUIRED_BY}"
+		origin=`origin_from_pdb $dir`
+
+		deplist=`grep DEPORIGIN:$origin$ $pdb/*/+CONTENTS`
+		if [ -z "$deplist" ]; then
+			echo -n "===>>> ${dir#$pdb/} is no longer depended on, delete? [n] "
+			read YESNO
+
+			case "$YESNO" in
+			[yY])	pkg_delete ${dir#$pdb/} ;;
+			esac
+		else
+			echo "===>>> Warning: unrecorded dependencies on ${dir#$pdb/}:"
+			echo $deplist
+		fi
+	done
+
+	exit 0
+fi
+
 test -n "$FORCE" && unset INTERACTIVE_UPDATE
 if [ -n "$UNATTENDED" ]; then
 	unset INTERACTIVE_UPDATE
@@ -468,7 +529,7 @@ if [ -n "$UPDATE_ALL" ]; then
 	if [ -n "$CONFIG_SEEN_LIST" ]; then
 		echo "===>>> Checking ports for recursive 'make config'"
 		for pkg in $roots $trunks $branches $leaves; do
-			p=`grep ' ORIGIN' $pkg/+CONTENTS | cut -f2 -d':'`
+			p=`origin_from_pdb $pkg`
 			if [ `grep "${pd}/${p}$" $CONFIG_SEEN_LIST` ]; then
 				continue
 			else
@@ -480,6 +541,7 @@ if [ -n "$UPDATE_ALL" ]; then
 		unset_recursive_config
 		echo ''
 		echo "===>>> Starting build for ports that need updating <<<==="
+		echo ''
 	fi
 
 	for pkg in $roots $trunks $branches $leaves; do
@@ -489,7 +551,7 @@ if [ -n "$UPDATE_ALL" ]; then
 			continue
 		fi
 		if [ -n "$FORCE" ]; then
-			p=`grep ' ORIGIN' $pkg/+CONTENTS | cut -f2 -d':'`
+			p=`origin_from_pdb $pkg`
 			if [ ! `grep "${pd}/${p}$" $UPDATES_DONE_LIST` ]; then
 				echo "===>>> Forcing update for ${pkg##*/}"
 				update_port ${pkg##*/}
@@ -508,23 +570,42 @@ if [ -n "$UPDATE_ALL" ]; then
 	safe_exit
 fi
 
+if [ -n "$REPLACE_ORIGIN" ]; then
+	portdir="${1#$pd/}"
+	newportdir=$portdir
+
+	if [ -d "$pdb/$2" ]; then
+		# Handle the portmaster'ish way to specify the port
+		upg_port=$2
+	else
+		# Handle existing portupgrade syntax
+		upg_port=`grep -l " ORIGIN:[^\/]*/${2}$" $pdb/*/+CONTENTS`
+		[ -n "$upg_port" ] ||
+		    upg_port=`grep -l " ORIGIN:[^\/]*/${2}" $pdb/*/+CONTENTS`
+		[ -n "$upg_port" ] ||
+		    fail "Cannot find an installed port with ORIGIN $2"
+		upg_port="${upg_port%/+CONTENTS}"
+		upg_port="${upg_port#$pdb/}"
+	fi
+
+	oldportdir=`origin_from_pdb $pdb/$upg_port`
+fi
+
 # Exercised in the common case of not using -p option
 case "$portdir" in
-'')	eval arg=\$${OPTIND}
-	case "${arg}" in
+'')	case "$1" in
 	'')	test -z "$UPDATE_REQ_BYS" && usage ;;
-	${pd}/*)	portdir="${arg#$pd/}" ;;
-	/*)	upg_port="${arg##*/}" ;;
-	*)	upg_port=$arg ;;
+	${pd}/*)	portdir="${1#$pd/}" ;;
+	/*)	upg_port="${1##*/}" ;;
+	*)	upg_port=$1 ;;
 	esac
 esac
 
 case "$upg_port" in
 '')	test -n "$portdir" || usage
-	old_port_dir=`grep -l "@comment ORIGIN:${portdir}$" $pdb/*/+CONTENTS`
+	old_port_dir=`iport_from_origin ${portdir}`
 	if [ -n "$old_port_dir" ]; then
-		old_port_dir="${old_port_dir%/+CONTENTS}"
-		upg_port="${old_port_dir#$pdb/}"
+		upg_port="${old_port_dir}"
 	fi
 	;;
 *)	if [ ! -d "$pdb/$upg_port" ]; then
@@ -546,7 +627,11 @@ case "$upg_port" in
 		esac
 	fi
 	echo "===>>> Port to upgrade: $upg_port"
-	portdir=`grep ' ORIGIN' $pdb/$upg_port/+CONTENTS | cut -f2 -d':'`
+	if [ -z "$portdir" ]; then
+		portdir=`origin_from_pdb $pdb/$upg_port`
+		[ -n "$portdir" ] ||
+		    fail "No ORIGIN in $pdb/$upg_port/+CONTENTS"
+	fi
 	;;
 esac
 
@@ -574,7 +659,7 @@ if [ -n "$CONFIG_ONLY" ]; then
 		safe_exit
 	else
 		if [ -n "$UPDATE_REQ_BYS" -a \
-		    -r "$pdb/$upg_port/+REQUIRED_BY" ]; then
+		    -s "$pdb/$upg_port/+REQUIRED_BY" ]; then
 			echo "$pd/$portdir" >> $CONFIG_SEEN_LIST
 
 			echo ''
@@ -621,7 +706,7 @@ cd $pd/$portdir
 while [ -f "$fetchlog" ]; do
 	echo ''
 	echo "===>>> Waiting on fetch to complete for $portdir <<<==="
-	tail -10 $fetchlog | grep -v '^$'
+	tail -10 $fetchlog 2>/dev/null | grep -v '^$'
 	echo ''
 	echo "===>>> Waiting on fetch to complete for $portdir <<<==="
 	sleep 5
@@ -637,8 +722,12 @@ short_port="${prefix}${portname}${suffix}"
 
 # Check for dependencies here in case +REQUIRED_BY is not up to date or missing
 grep_deps=`mktemp -t grep-deps-${short_port}`
-grep -l "pkgdep ${upg_port%-*}-" $pdb/*/+CONTENTS | cut -f 5 -d '/' |
-    sort -u > $grep_deps
+
+if [ -n "$upg_port" ]; then
+	upg_origin=`origin_from_pdb $pdb/$upg_port`
+	grep -l DEPORIGIN:$upg_origin$ $pdb/*/+CONTENTS | cut -f 5 -d '/' |
+	    sort -u > $grep_deps
+fi
 
 if [ -s "$pdb/$upg_port/+REQUIRED_BY" ]; then
 	req_deps=`mktemp -t req-deps-${short_port}`
@@ -674,10 +763,27 @@ fi
 
 # Ignore if no old port exists
 if [ -n "$upg_port" ]; then
+	if [ -n "$BACKUP" ]; then
+		echo "===>>> Creating a backup package for $upg_port in $HOME"
+		pkg_create -b $upg_port ||
+		    fail "Backup package creation failed for $upg_port"
+		mv ${upg_port}.* $HOME/
+	fi
 	pkg_delete -f $upg_port || fail 'pkg_delete failed'
 fi
 
-make $MAKE_ARGS install clean || fail 'installation of new port failed'
+aw=install
+fw=Installation
+if [ -n "$MAKE_PACKAGE" ]; then
+	aw=package
+	fw=Packaging
+	echo "===>>> Creating a package for $new_port in $HOME"
+fi
+make $MAKE_ARGS $aw clean || fail "$fw of new port failed"
+
+if [ -n "$MAKE_PACKAGE" ]; then
+	mv ${new_port}.* $HOME/
+fi
 
 # By now, if this file exists, it should be authoritative
 if [ -s "$req_deps" ]; then
@@ -703,10 +809,17 @@ echo "===>>> Upgrade for $upg_port to $new_port succeeded"
 
 test -n "$UPDATES_DONE_LIST" && echo "$pd/$portdir" >> $UPDATES_DONE_LIST
 
-if [ -z "$DONT_SCRUB_DISTFILES" ]; then
+find_distdir () {
 	distdir=`make $MAKE_ARGS -V DISTDIR`
 	dist_subdir=`make $MAKE_ARGS -V DIST_SUBDIR`
 	test -n "$dist_subdir" && distdir="${distdir}/${dist_subdir}"
+}
+
+delete_stale_distfiles () {
+	# distfiles is used below
+	local distfile file DELORNOT
+
+	find_distdir
 
 	distfiles=`make $MAKE_ARGS -V DISTFILES`
 	cd $distdir || fail "cd to $distdir failed!"
@@ -738,9 +851,39 @@ if [ -z "$DONT_SCRUB_DISTFILES" ]; then
 			esac
 		done
 	done
+}
+
+if [ -z "$DONT_SCRUB_DISTFILES" ]; then
+	if [ -z "$oldportdir" ]; then
+		delete_stale_distfiles
+	else
+		if ! cd $pd/$oldportdir; then
+			echo "===>>> No $oldportdir to cd to in order to delete"
+			echo "       old distfiles, remove by hand if desired"
+		else
+		echo -n "===>>> Delete all distfiles for ${oldportdir#*/}? [n] "
+			read DELORNOT
+			case "$DELORNOT" in
+			[yY])	find_distdir
+				if [ -n "$dist_subdir" ]; then
+					cd $distdir && rm -r *
+				else
+					delete_stale_distfiles
+					rm $distfiles
+				fi
+				;;
+			echo "===>>> Deleting empty directories (if any)"
+				find $pd/distfiles -type d -empty -print -delete
+				;;
+			*)	delete_stale_distfiles ;;
+			esac
+		fi
+
+		cd $pd/$newportdir && delete_stale_distfiles
+	fi
 fi
 
-if [ -n "$UPDATE_REQ_BYS" -a -r "$pdb/$new_port/+REQUIRED_BY" ]; then
+if [ -n "$UPDATE_REQ_BYS" -a -s "$pdb/$new_port/+REQUIRED_BY" ]; then
 	echo ''
 	echo "===>>> Updating ports that depend on $new_port"
 	for req_by in `cat $pdb/$new_port/+REQUIRED_BY`; do