source: SaveSpace.git/hooks/pre-receive.sample

#!/bin/sh
#
# An example hook script to make use of push options.
# The example simply echoes all push options that start with 'echoback='
# and rejects all pushes when the "reject" push option is used.
#
# To enable this hook, rename this file to "pre-receive".

if test -n "$GIT_PUSH_OPTION_COUNT"
then
        i=0
        while test "$i" -lt "$GIT_PUSH_OPTION_COUNT"
        do
                eval "value=\$GIT_PUSH_OPTION_$i"
                case "$value" in
                echoback=*)
                        echo "echo from the pre-receive-hook: ${value#*=}" >&2
                        ;;
                reject)
                        exit 1
                esac
                i=$((i + 1))
        done
fi