added some more functionality

Added help section.
Added getops for options.
Added -a for auto update
Added -n for no updates.
Added $1 use to filter what containers.

dockcheck.sh

@@ -1,5 +1,36 @@
 #!/bin/bash
 
+# Help Function:
+Help() {
+  echo "Syntax:     dockcheck.sh [OPTION] [part of name to filter]" 
+  echo "Example:    dockcheck.sh -a ng"
+  echo
+  echo "Options:"
+  echo "-h     Print this Help."
+  echo "-a     Automatic updates, without interaction."
+  echo "-n     No updates, only checking availability."
+}
+
+while getopts "anh" options; do
+  case "${options}" in
+    a)
+      UpdYes="yes"
+      ;;
+    n)
+      UpdYes="no"
+      ;;
+    h|*) # help or unknown option:
+      Help
+      exit 0;;
+  esac
+done
+
+### Set $1 back to $1 (ignoring the places held by getops)
+shift "$((OPTIND-1))"
+
+### Set $1 to a variable for later
+SearchName="$1"
+
 ### Check if required binary exists in PATH or directory:
 if [[ $(builtin type -P "regctl") ]]; then 
   regbin="regctl"
@@ -26,9 +57,8 @@ else
   fi
 fi
 
-
 ### Check the image-hash of every running container VS the registry
-for i in $(docker ps --format '{{.Names}}') 
+for i in $(docker ps --filter "name=$SearchName" --format '{{.Names}}') 
 do
 printf ". "
   RepoUrl=$(docker inspect "$i" --format='{{.Config.Image}}')
@@ -53,8 +83,10 @@ fi
 
 ### Optionally get updates if there's any 
 if [ -n "$GotUpdates" ] ; then
+  if [ -z "$UpdYes" ] ; then
   printf "\n\033[36;1mDo you want to update? y/[n]\033[0m\n"
   read UpdYes
+    else
     if [ "$UpdYes" != "${UpdYes#[Yy]}" ] ; then
       for i in "${GotUpdates[@]}"
       do 
@@ -67,7 +99,7 @@ if [ -n "$GotUpdates" ] ; then
     else
       printf "\nNo updates installed, exiting.\n"
     fi
+  fi
 else
   printf "\nNo updates available, exiting.\n"
 fi
-