Add sysusers group and be a little more zealous about removing attrs

.SRCINFO

@@ -1,7 +1,7 @@
 pkgbase = nordvpn-bin
 	pkgdesc = NordVPN CLI tool for Linux
 	pkgver = 3.8.8
-	pkgrel = 1
+	pkgrel = 2
 	url = https://nordvpn.com/download/linux/
 	install = nordvpn-bin.install
 	arch = x86_64

PKGBUILD

@@ -4,7 +4,7 @@
 
 pkgname=nordvpn-bin
 pkgver=3.8.8
-pkgrel=1
+pkgrel=2
 pkgdesc="NordVPN CLI tool for Linux"
 arch=('x86_64' 'i686' 'armv7h' 'aarch64')
 url="https://nordvpn.com/download/linux/"

nordvpn-bin.install

@@ -1,6 +1,16 @@
 post_install() {
   echo ':: In order to enable nordvpn you have to start the following service:'
   echo '     sudo systemctl enable --now nordvpnd'
+  echo ':: You have to add yourself to the nordvpn group to use it:'
+  echo "     gpasswd -a USERNAME nordvpn"
+}
+
+pre_install() {
+  chattr -i /var/lib/nordvpn/data/*
+}
+
+pre_upgrade() {
+  chattr -i /var/lib/nordvpn/data/*
 }
 
 pre_remove() {