timelapse.sh

#!/bin/bash
SCREEN_COUNT=0
echo Capture started on `date`
echo Capture started on `date` >> log.txt
trap ctrl_c INT
function ctrl_c() {
  echo Capture ended on `date` with $SCREEN_COUNT screens captured.
  echo Capture ended on `date` with $SCREEN_COUNT screens captured. >> log.txt
  exit
}
while true
do
  sleep 30
  FILENAME=screens/screen.`date +%s`.jpg
  echo Capturing to $FILENAME
  screencapture -C -m -t jpg -x -f $FILENAME
  SCREEN_COUNT=$((SCREEN_COUNT+1))
done