[SOLVED] Simple question about pkgtools

Kallaste · 07-01-2012, 01:56 PM

Hi,

The following is a description of the updatepkg application taken directly from the Intro to Slackware page at Linux.com:

https://www.linux.com/learn/tutorials/261878-intro-to-slackware-package-management/

Quote:

upgradepkg - upgradepkg upgrades a Slackware package from an older version to a newer one.¬† It does this by INSTALLING the new package onto the system, and then REMOVING any files from the old package that aren't in the new package (taken from the man pages)

I am just a bit confused by this and I hope someone can help me understand what happens. Why would the application remove files from the old package that aren't in the new package? Wouldn't that just leave everyone with two copies of every file that ARE in the new package--one from the old version and one from the new?

And how is it that files that the upgrade does NOT contain are safe to remove?

Forgive me if these are newbie questions, but I want to understand.

Thank you.

whizje · 07-01-2012, 02:08 PM

Quote:

Why would the application remove files from the old package that aren't in the new package?

Because the new package don't needs them.

Quote:

Wouldn't that just leave everyone with two copies of every file that ARE in the new package--one from the old version and one from the new?

No the new files replace the old files.

Quote:

And how is it that files that the upgrade does NOT contain are safe to remove?

Because a package is a whole unit. upgradepkg is a convenient way of running removepkg and installpkg.

s1aw0 · 07-01-2012, 03:30 PM

BloomingNutria, the quote is actually taken from upgradepkg itself. To see it, just run upgradepkg w/o any argument. And upgradepkg is a clearly written bash shell script, so that you can study how it works and even modify it.

Kallaste · 07-01-2012, 03:45 PM

@whizje: Oh, I see, thank you!

@s1aw0: I will give it a look.

Thanks!