#!/bin/sh

# This script is a template for a self modifiying script

# License: LGPLv2

# Change the following to whatever
# method updates your script, for e.g.
#     svn update $0
proc update_method {
    return
}
# Note the exec must be read from disk
# before updated_method is called, hence
# why update_this_script is in a function.
proc update_this_script {
    setglobal old_md5 = $[md5sum $0 | cut -d' ' -f1]
    update_method
    setglobal new_md5 = $[md5sum $0 | cut -d' ' -f1]
    if test $old_md5 != $new_md5 {
        exec $0 @ARGV
    }
}
update_this_script

echo "rest of script here"