Linux RPM check Atom update

atom_update_check.sh

#!/bin/sh

NOTIFY_USER=oleg # optional, for kdialog
USER_DISPLAY=:0  # optional, for kdialog


LOCATION=`curl -I https://github.com/atom/atom/releases/latest | perl -n -e '/^Location: (.*)$/ && print "$1"'`
VERSION=`basename $LOCATION | perl -n -e '/(\d+.\d+.\d+)/ && print "$1"'`
echo "available version: $VERSION"
INSTALLED=`rpm -q atom | perl -n -e '/atom-(.*?)-/ && print "$1"'`
echo "installed version: $INSTALLED"


if [ "$INSTALLED" != "$VERSION" ]; then
  echo "version $VERSION available"
  sudo -u $NOTIFY_USER DISPLAY=$USER_DISPLAY kdialog --title "Atom update" --passivepopup "$VERSION is available ($INSTALLED installed) <a href=$LOCATION>download</a>" 10 # optional
  exit 0
else
  exit 126
fi