README for tlp 1.0-1 in Debian
==============================

Backporting to versions older than Jessie
-----------------------------------------

Release 1.0-1 of TLP introduces some changes in the building process that need
to be reverted in case you want to backport it to Wheezy or older versions of
Debian.

First, it needs dh-systemd, which used to be available in its own package, but
has been merged in debhelper 9.20160709. Suitable versions are available in
Stretch, and in Jessie backports, but not in Wheezy.

Furthermore, the documentation directory of tlp-rdw has become a symlink
pointing to tlp. This change requires a "dir to symlink" migration, which is
supported by dpkg starting with version 1.17.14. Again, suitables versions are
available in both Stretch and Jessie, but not in Wheezy.

Finally, dh_installinit option --onlyscripts changed to --only-scripts in
debhelper 10.1.

Official backports of this package are released for stable and oldstable
(Stretch and Jessie at the time of writing), but since only security updates
are officially released in LTS, you'll have to build the package yourself if
you want to backport it.

The Git repository on collab-maint has a branch named "debian/wheezy-lts" which
already contains the needed changes, so you can use it as-is to build your own
package for Wheezy.  If you want to backport the package to an even older
release, you can use it as a base, but you're on your own.

Downgrades
----------

Downgrades are not supported in Debian. They usually work, but not always. In
the case of a "dir to symlink" migration, the downgrade will seem to work, but
the symlink won't be converted back to a directory. Worse, an upgrade following
a downgrade may leave the target directory in an inconsistent state (but a
second upgrade seems to fix that).

The bottom line is that if you want to downgrade to a version older than 1.0-1,
you should rather purge both tlp and tlp-rdw and re-install them, than
downgrade them.
