idleLock.sh

#!/bin/sh

# add alias="bash ~/idleLock.sh" to your .bashrc
# thefted from https://apple.stackexchange.com/questions/206942/detect-mouse-move-or-keystroke

# Pause/Interval between checks
checkInt=.1

# Keep track of the idle timer
lastIdle=0

while true ; do
   ioresp=`ioreg -w 0 -c IOHIDSystem | sed -e '/HIDIdleTime/ !{ d' -e 't' -e '}' -e 's/.* = //g' -e 'q'`
   idleNow=`echo $(( ${ioresp} / 1000000000 ))`

   re='^[0-9]+$'
   if ! [[ $idleNow =~ $re ]] ; then
      echo "error: ioreg did not return a number" >&2; exit 1
   fi

   # if idle decreased then action occurred so we do something...
   if [ $idleNow -lt $lastIdle ] ; then
      /System/Library/CoreServices/"Menu Extras"/User.menu/Contents/Resources/CGSession -suspend
      exit 1
   else
      lastIdle=$idleNow
   fi

   sleep