A poor woman's filesystem watcher

usage.md

To use watchman, run watchman file-to-watch sleep-time command-to-execute like so.

watchman test.txt 1 echo 'Tada!'

watchman.fish

function watchman --description "watchman <file> <wait-time> <command>"
    set initial_time (stat -f '%Z' $argv[1])
    while true
        set changed_time (stat -f '%Z' $argv[1])
        if [ $initial_time != $changed_time ]
            eval $argv[3..-1]
            set initial_time $changed_time
        end
        sleep $argv[2]
    end
end

watchman.sh

function watchman {
    initial_time=$(stat -f '%Z' $1)
    while true; do
        changed_time=$(stat -f '%Z' $1)
        if [ $initial_time != $changed_time ]; then
            eval ${@:3}
            initial_time=$changed_time
        fi
        sleep $2
    done
}