deb-preinst - package pre-installation maintainer script
A package can perform several pre-installation actions via maintainer scripts,
by including an executable preinst file in its control archive (i.e.
DEBIAN/preinst during package creation).
The script can be called in the following ways:
- new-preinst install
- Before the package is installed.
- new-preinst install old-version new-version
- Before removed package is upgraded.
- new-preinst upgrade old-version new-version
- Before the package is upgraded.
- old-preinst abort-upgrade new-version
- If postrm fails during upgrade or fails on failed upgrade.