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+# TODO
+
+## easy cert revocation
+
+here comes an example for watching file changes  
+the idea is to extend the step-ca container to be able to revoke certificates easily.  
+not that i think this is needed 0:-)
+
+source: https://stackoverflow.com/questions/22884580/bash-a-way-to-watch-files-for-changes#22885210
+
+```bash
+#!/bin/bash
+
+watched_files=$@  # pass watched files as cmd line arguments
+
+if [ -z "$watched_files" ]; then
+  echo "Nothing to watch, abort"
+  exit
+else
+  echo "watching: $watched_files"
+fi
+
+previous_checksum="dummy"
+while [ 1 ]; do
+  checksum=$(md5sum $watched_files | md5sum)
+  if [ "$checksum" != "$previous_checksum" ]; then
+    echo "None shall pass!"  # do your stuff here
+  fi
+  previous_checksum="$checksum"
+  sleep 1
+done
+```