On Tue, Oct 26, 2021 at 10:31:54AM -0700, Han wrote: > Hi, > > This might be a dumb question: is dpkg installing (or updating) a package > using a .deb file atomic in the event of power outage? > > By atomic, I meant either the new version of the application is fully > installed, or not at all. Is this always guaranteed?
No. A package can be in a "half-installed" state. unicorn:~$ dpkg -l | head -n3 Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) See where it says "Half-inst" in the middle? If an "H" is shown in that column, the package is half-installed. Also, the post-install scripts that most packages use are shell scripts, so you already know a priori that the script could be interrupted partway through.
