--- a/sbin/fjail	Sun Aug 21 11:19:47 2022 +0200
+++ b/sbin/fjail	Sun Aug 21 11:43:01 2022 +0200
@@ -395,7 +395,8 @@
     _rootds_mountpoint="$(zfs list -H -o mountpoint -t filesystem "${_dsname}")"  || \
         { echo "ERROR: root dataset does not exist" >&2; return 1; }
 
-    zfs list -H -o name,mountpoint,canmount,mounted -s mountpoint -t filesystem -r "${_dsname}" | \
+    zfs list -H -o name,mountpoint,canmount,mounted -s mountpoint -t filesystem -r "${_dsname}" \
+    | {
         while IFS=$'\t' read -r _name _mp _canmount _mounted ; do
             # Skip filesystems that are already mounted
             [ "${_mounted}" = "yes" ] && continue
@@ -432,7 +433,8 @@
             esac
         done
 
-    return 0
+        return 0
+    }
 }
 
 
@@ -453,14 +455,16 @@
     # Just determine whether the given dataset name exists
     _rootds_mountpoint="$(zfs list -H -o mountpoint -t filesystem "${_dsname}")" || { echo "ERROR: dataset not found" >&2; return 1; }
 
-    mount -t zfs -p | \
-        grep -E "^${_dsname}(/|\s)" | \
-        sort -n -r | \
+    mount -t zfs -p \
+    | grep -E "^${_dsname}(/|\s)" \
+    | sort -n -r \
+    | {
         while IFS=' '$'\t' read -r _name _mp _rest ; do
             echo "Umounting ${_name} on ${_mp}"
             umount "${_mp}" || return 1
         done
-    return 0
+        return 0
+    }
 }