throttle in bash

throttle.sh

#!/bin/bash

# usage: throttle.sh FILENAME THROTTLE_SECONDS CMD [ARGS...]
# example usage: while sleep .1; do throttle.sh /tmp/date 1 date +%s.%N; done

FILENAME=$1
THROTTLE_SECONDS=$2
shift 2

last_called=$(<$FILENAME)
if [[ -z "$last_called" ]]; then
  last_called=$EPOCHSECONDS
fi
if ((EPOCHSECONDS - last_called >= THROTTLE_SECONDS)); then
  "$@"
fi
echo $EPOCHSECONDS > $FILENAME