Remove basename(1). Clean up/shorten some coreutils pipelines

Basenames that remain, in cmd/zed/zed.d/statechange-led.sh:
	dev=$(basename "$(echo "$therest" | awk '{print $(NF-1)}')")
	vdev=$(basename "$ZEVENT_VDEV_PATH")
I don't wanna interfere with #11988

scripts/zfs-tests.sh:
	SINGLETESTFILE=$(basename "$SINGLETEST")
tests/zfs-tests/tests/functional/cli_user/zfs_list/zfs_list.kshlib:
	ACTUAL=$(basename $dataset)
	ACTUAL=$(basename $dataset)
tests/zfs-tests/tests/functional/cli_user/zpool_iostat/
	zpool_iostat_-c_homedir.ksh:
	typeset USER_SCRIPT=$(basename "$USER_SCRIPT_FULL")
tests/zfs-tests/tests/functional/cli_user/zpool_iostat/
	zpool_iostat_-c_searchpath.ksh:
	typeset CMD_1=$(basename "$SCRIPT_1")
	typeset CMD_2=$(basename "$SCRIPT_2")
tests/zfs-tests/tests/functional/cli_user/zpool_status/
	zpool_status_-c_homedir.ksh:
	typeset USER_SCRIPT=$(basename "$USER_SCRIPT_FULL")
tests/zfs-tests/tests/functional/cli_user/zpool_status/
	zpool_status_-c_searchpath.ksh
	typeset CMD_1=$(basename "$SCRIPT_1")
	typeset CMD_2=$(basename "$SCRIPT_2")
tests/zfs-tests/tests/functional/migration/migration.cfg:
	export BNAME=`basename $TESTFILE`
tests/zfs-tests/tests/perf/perf.shlib:
	typeset logbase="$(get_perf_output_dir)/$(basename \
tests/zfs-tests/tests/perf/perf.shlib:
	typeset logbase="$(get_perf_output_dir)/$(basename \

These are potentially Of Directories, where basename is actually
useful

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12652

cmd/zpool/zpool.d/dm-deps

@@ -16,14 +16,12 @@ if [ -L "$dev" ] ; then
 	dev=$(readlink "$dev")
 fi
 
-dev=$(basename "$dev")
+dev="${dev##*/}"
 val=""
 if [ -d "/sys/class/block/$dev/slaves" ] ; then
-	# ls -C: output in columns, no newlines
-	val=$(ls -C "/sys/class/block/$dev/slaves")
-
-	# ls -C will print two spaces between files; change to one space.
-	val=$(echo "$val" | sed -r 's/[[:blank:]]+/ /g')
+	# ls -C: output in columns, no newlines, two spaces (change to one)
+	# shellcheck disable=SC2012
+	val=$(ls -C "/sys/class/block/$dev/slaves" | tr -s '[:space:]' ' ')
 fi
 
 echo "dm-deps=$val"

cmd/zpool/zpool.d/iostat

@@ -9,7 +9,7 @@ iostat:		Show iostat values since boot (summary page).
 iostat-1s:	Do a single 1-second iostat sample and show values.
 iostat-10s:	Do a single 10-second iostat sample and show values."
 
-script=$(basename "$0")
+script="${0##*/}"
 if [ "$1" = "-h" ] ; then
 	echo "$helpstr" | grep "$script:" | tr -s '\t' | cut -f 2-
 	exit
@@ -42,7 +42,7 @@ else
 		${brief:+"-y"} \
 		${interval:+"$interval"} \
 		${interval:+"1"} \
-		"$VDEV_UPATH" | awk NF | tail -n 2)
+		"$VDEV_UPATH" | grep -v '^$' | tail -n 2)
 fi
 
 
@@ -61,7 +61,7 @@ fi
 cols=$(echo "$out" | head -n 1)
 
 # Get the values and tab separate them to make them cut-able.
-vals=$(echo "$out" | tail -n 1 | sed -r 's/[[:blank:]]+/\t/g')
+vals=$(echo "$out" | tail -n 1 | tr -s '[:space:]' '\t')
 
 i=0
 for col in $cols ; do

cmd/zpool/zpool.d/lsblk

@@ -48,7 +48,7 @@ size:	Show the disk capacity.
 vendor:	Show the disk vendor.
 lsblk:	Show the disk size, vendor, and model number."
 
-script=$(basename "$0")
+script="${0##*/}"
 
 if [ "$1" = "-h" ] ; then
         echo "$helpstr" | grep "$script:" | tr -s '\t' | cut -f 2-

cmd/zpool/zpool.d/media

@@ -9,15 +9,12 @@ if [ "$1" = "-h" ] ; then
 fi
 
 if [ -b "$VDEV_UPATH" ]; then
-	device=$(basename "$VDEV_UPATH")
-	val=$(cat "/sys/block/$device/queue/rotational" 2>/dev/null)
-	if [ "$val" = "0" ]; then
-		MEDIA="ssd"
-	fi
-
-	if [ "$val" = "1" ]; then
-		MEDIA="hdd"
-	fi
+	device="${VDEV_UPATH##*/}"
+	read -r val 2>/dev/null < "/sys/block/$device/queue/rotational"
+	case "$val" in
+		0) MEDIA="ssd" ;;
+		1) MEDIA="hdd" ;;
+	esac
 
 	vpd_pg83="/sys/block/$device/device/vpd_pg83"
 	if [ -f "$vpd_pg83" ]; then

cmd/zpool/zpool.d/ses

@@ -11,7 +11,7 @@ fault_led:	Show value of the disk enclosure slot fault LED.
 locate_led:	Show value of the disk enclosure slot locate LED.
 ses:		Show disk's enc, enc device, slot, and fault/locate LED values."
 
-script=$(basename "$0")
+script="${0##*/}"
 if [ "$1" = "-h" ] ; then
 	echo "$helpstr" | grep "$script:" | tr -s '\t' | cut -f 2-
 	exit