Check shellscript - check is running

check_is_running.sh

#!/bin/bash
#
lockdir=/tmp/diario_stocks.lock
 if mkdir "$lockdir"
 then
     echo >&2 "successfully acquired lock"

     # Remove lockdir when the script finishes, or when it receives a signal
     trap 'rm -rf "$lockdir"' 0    # remove directory when script finishes

     # Optionally create temporary files in this directory, because
     # they will be removed automatically:
     # tmpfile=$lockdir/filelist

 else
     echo >&2 "cannot acquire lock, giving up on $lockdir"
     exit 0
 fi