More slight refactoring; shows root file system free space before upgrade; deals with older hardlink.

README.md

@@ -17,8 +17,13 @@ using **`apt`** and also, when present, `snap`, `flatpak` and `fwupdmgr`.
 - [`flatpak`](https://packages.debian.org/stable/flatpak)
 - [`fwupd`](https://packages.debian.org/stable/fwupd)
 - from [`util-linux`](https://packages.debian.org/stable/util-linux):
-	- [`ionice`](https://manpages.debian.org/stable/util-linux/ionice.1) for running the tool with lowest I/O priority
-	- [`hardlink`](https://manpages.debian.org/stable/util-linux/hardlink.1) for linking identical files in APT lists directory, saving space
+	- [`ionice`](https://manpages.debian.org/stable/util-linux/ionice.1)
+	for running the tool with lowest I/O priority.
+	- [`hardlink`](https://manpages.debian.org/stable/util-linux/hardlink.1)
+	for linking identical files in APT lists directory, saving space.
+		- Until Debian 11 "bullseye" (or [Ubuntu 20.04](https://packages.ubuntu.com/focal/hardlink)),
+		this was a different program, from package [`hardlink`](https://packages.debian.org/bullseye/hardlink) ([manpage](https://manpages.debian.org/bullseye/hardlink/hardlink.1.en.html)),
+		less tested here.
 
 ## Usage
 

sub_apt-upgrade.sh

@@ -19,11 +19,13 @@
 # with this program. If not, see <http://www.gnu.org/licenses/>.
 
 FORCE_IPV4="-o Acquire::ForceIPv4=true"
-
 ORIG_UID=${ORIG_UID:-$UID}
+PARAMETERS="${*:-\"\"}"
+
+[[ "$PARAMETERS" == *'-v'* ]] && echo "Script called with parameters: $PARAMETERS"
 
 if [ -z "$MY_USER" ] ; then
-	[[ "$*" == *'-v'* ]] && echo "ORIG_UID=$ORIG_UID"
+	[[ "$PARAMETERS" == *'-v'* ]] && echo "ORIG_UID=$ORIG_UID"
 
 	if [ "$ORIG_UID" -ne 0 ] ; then
 		MY_USER=$(logname 2> /dev/null)
@@ -31,6 +33,8 @@ if [ -z "$MY_USER" ] ; then
 	fi
 fi
 
+export FORCE_IPV4 ORIG_UID PARAMETERS MY_USER
+
 check_apt () {
 	APT_CMD="${APT_CMD:-apt}"
 
@@ -46,7 +50,7 @@ check_apt () {
 	[[ "$PARAMETERS" == *'-nu'* ]] || [[ "$PARAMETERS" == *'--no-update'* ]]
 	SKIP_UPDATE=$?
 
-	if [ "$SKIP_UPDATE" = 0 ] ; then
+	if [ "$SKIP_UPDATE" -eq 0 ] ; then
 		echo "Skipping $APT_CMD update as requested."
 	else
 		[[ "$APT_CMD" == 'nala' ]] && UPD_PARAMS="$UPD_PARAMS -v"
@@ -78,7 +82,8 @@ check_apt () {
 		if command -v hardlink > /dev/null 2>&1 && [ -e "$APT_LISTS_DIR" ] ; then
 			echo "* Linking identical files in APT lists directory \"$APT_LISTS_DIR\" ..."
 			echo
-			hardlink --ignore-time --respect-xattrs --reflink=auto "$APT_LISTS_DIR"
+			hardlink --ignore-time --respect-xattrs "$APT_LISTS_DIR"
+			# --reflink=auto is available only on util-linux' hardlink
 		else
 			echo "WARNING: there is no command \"hardlink\" or directory \"$APT_LISTS_DIR\"."
 		fi
@@ -104,6 +109,9 @@ check_apt () {
 			echo "Warning: unexpected APT_CMD \"$APT_CMD\""
 			;;
 	esac
+
+	echo
+	echo "$FREE_MSG $(free_space||true)"
 	
 	[[ "$PARAMETERS" == *'-4'* ]] && APT_PARAMS="$APT_PARAMS $FORCE_IPV4"
 	[[ "$PARAMETERS" == *'-y'* ]] && APT_PARAMS="$APT_PARAMS -y"
@@ -213,13 +221,13 @@ check_fwupd () {
 #	fi
 #}
 
-freeSpace () {
+free_space () {
 	df --sync --output=avail -h / | tail -1
 }
 
 startup () {
 	UPTIME_BEGIN=$(uptime)
-	DF_BEGIN=$(freeSpace)
+	DF_BEGIN=$(free_space)
 	echo
 	check_apt && { check_snap ; check_flatpak ; check_fwupd ; }
 	#flashToFirefoxSnap # deprecated
@@ -227,14 +235,11 @@ startup () {
 	echo "Start:$UPTIME_BEGIN"
 	echo "  end:$(uptime)"
 	echo
-	echo Root file system free space:
+	echo "$FREE_MSG"
 	echo "$DF_BEGIN before"
-	echo "$(freeSpace||true) after"
+	echo "$(free_space||true) after"
 }
 
-export PARAMETERS="${*:-\"\"}"
-[[ "$PARAMETERS" == *'-v'* ]] && echo "Script called with parameters: $PARAMETERS"
-
 if [[ "$PARAMETERS" == *'--help'* ]] ; then
 	echo "Updates the system: apt [or nala if present] (update/upgrade/autoremove/clean), snap, flatpak and fwupdmgr (if present)."
 	echo
@@ -253,6 +258,7 @@ if [[ "$PARAMETERS" == *'--help'* ]] ; then
 	echo "	[ -vv ] . . . . . . . Also use \"bash -x\" to run the script."
 	echo "	[ --help ]  . . . . . Display this help text and exits."
 else
+	export FREE_MSG='Root file system free space:'
 	startup
 fi