Clean up

start-vnc

@@ -64,7 +64,7 @@ SVNC_ACCTCODE=""
 #
 # Specify your username on the login node if it is not your local
 # username.
-SVNC_USERNAME=$(id -un)
+SVNC_USERNAME="$(id -un)"
 
 # Path to local vncviewer
 #
@@ -142,17 +142,29 @@ clean_up () {
 }
 
 usage () {
-    printf "Usage: %s [OPTIONS]\n" $(basename $0) >&2
-    printf -- "-u username\n-A acctcode\n-g geometry\n-n nodes\n" >&2
-    printf -- "-q qos\n-t time\n-v path_to_vncviewer\n" >&2
-    printf -- "-x vncviewer_options\n" >&2
+    cat <<EOF
+Usage: $(basename "$0") [OPTION]
+
+Available values for OPTION include:
+
+  -A acctcode  acctcode of job
+  -g geometry  initial geometry of vnc window
+  -n nodes     number of nodes
+  -q qos       job qos
+  -t time      job runtime
+  -u username  use username for login
+  -v path      path to vncviewer program
+  -x options   addidtional options for vncviewer
+
+EOF
 }
 
 ssh_frontend () {
     local command="$1"
     local extra_options="${2:-}"
-    local options="${extra_options} -o ForwardX11=no \
-          -o ControlPath=${ssh_socket_dir}/control:%h:%p:%r"
+    local options
+    options="${extra_options} -o ForwardX11=no \
+            -o ControlPath=${ssh_socket_dir}/control:%h:%p:%r"
     ssh ${options} "${SVNC_USERNAME}@${SVNC_FRONTEND_HOST}" "${command}"
 }
 
@@ -208,10 +220,11 @@ prepare_vncserver () {
 }
 
 submit_vnc_job () {
+    local sbatch_resources
     if [[ ${SVNC_NODES} = "half" ]]; then
-        local sbatch_resources="#SBATCH --ntasks=24"
+        sbatch_resources="#SBATCH --ntasks=24"
     else
-        local sbatch_resources="#SBATCH --nodes=${SVNC_NODES}"
+        sbatch_resources="#SBATCH --nodes=${SVNC_NODES}"
         sbatch_resources+=$'\n#SBATCH --exclusive'
     fi
     ssh_frontend "cd .startvnc && sbatch" <<EOF
@@ -236,8 +249,8 @@ logfile=\${HOME}/.startvnc/out.${job_id}
 while [[ -z \${host_and_display} ]]; do
     sleep 1
     if [[ -f \${logfile} ]]; then
-        host_and_display=\$(grep -Po "started on display \Kmg[0-9]+:[0-9]+" \
-                          \${logfile})
+        host_and_display="\$(grep -Po "started on display \Kmg[0-9]+:[0-9]+" \
+                          \${logfile})"
     fi
     printf "." >&2
 done
@@ -250,22 +263,24 @@ main () {
     parse_options "$@"
     trap clean_up INT QUIT TERM ERR EXIT
 
-    ssh_socket_dir=$(mktemp -d "${HOME}/.ssh/socket.XXXXX")
+    ssh_socket_dir="$(mktemp -d "${HOME}/.ssh/socket.XXXXX")"
     ssh_frontend "" "-MNf"
     prepare_vncserver
 
     echo "Submitting vncserver job."
-    job_id=$(submit_vnc_job)
+    job_id="$(submit_vnc_job)"
 
     printf "Waiting for job ${job_id} to start" >&2
-    local host_and_display=$(get_vnc_host_and_display "$job_id")
+    local host_and_display
+    host_and_display="$(get_vnc_host_and_display "$job_id")"
     vnc_host=${host_and_display%:*}
     vnc_display=${host_and_display#*:}
     echo "Vncserver started on node ${vnc_host}.dkrz.de display \
 :${vnc_display}."
 
-    local vnc_options="${SVNC_VNC_OPTIONS:-} \
-                       -via ${SVNC_USERNAME}@${vnc_host}.dkrz.de"
+    local vnc_options
+    vnc_options="${SVNC_VNC_OPTIONS:-} \
+                -via ${SVNC_USERNAME}@${vnc_host}.dkrz.de"
     if [[ ${SVNC_PASSWORD} = "true" ]]; then
         echo "Fetching password from frontend."
         ssh_frontend "cat .vnc/passwd" > ${HOME}/vnc_passwd