Changes

  $ tar xvfz dolibarr.tgz

  $ tar xvfz dolibarr.tgz

* Copy all new extracted files (the one uncompressed into directory dolibarr-x.y.z) to the directory where you put your old Dolibarr version

* Copy all new extracted files (the one uncompressed into directory dolibarr-x.y.z) to the directory where you put your old Dolibarr version. This will overwrite old files with new ones without removing files specifics to your installation (like conf.php file or complementary non official installed modules).

  $ cp -r dolibarr-x.y.z/* dolibarr

  $ cp -r dolibarr-x.y.z/* dolibarr