ssh - fix unbound variable error

seqs/ssh.sh

@@ -78,10 +78,10 @@ step_10_info() {
 step_10_alias() { echo "sendlist"; }
 step_10() {
   shift
-  aList=$1
-  aHost=$2
+  aList=${1:-}
+  aHost=${2:-}
   # Set port only if not empty
-  if [ ! -z "$3" ]; then
+  if [ -n "${3:-}" ]; then
     aPort=$3
   fi
   parseList $aList
@@ -113,8 +113,8 @@ step_10() {
 parseList() {
   local errorMsg=""
 
-  if [ -z "$1" ] || [ ! -f "$1" ]; then
-    if [ -z "$1" ]; then
+  if [ -z "${1:-}" ] || [ ! -f "${1:-}" ]; then
+    if [ -z "${1:-}" ]; then
       error -e "No Command list found"
     else
       error -e "Command list not found: $1"
@@ -132,7 +132,7 @@ parseList() {
     return 1
   fi
 
-  info "Parsing $(realpath $1) ..."
+  info "Parsing $(realpath -- "${1:-}") ..."
   local line=1
   # Working loop without ssh "stealing standard input" by
   # https://unix.stackexchange.com/questions/24260/reading-lines-from-a-file-with-bash-for-vs-while