Arch Linux

uiii

Member

Registered: 2009-02-25

Posts: 27

Interrupt package uninstallation

Hi,
is it possible to interrupt an uninstallation of a package if a conditions are not met? E.g. if some environment variable is not set. I tried to put exit 1 or return 1 in the pre_remove, it will print error but the uninstallation continues. I need this because I'm doing some backup restore during uninstallation and I need a path to backup directory. Please do not tell me if this is good or bad it's only for my personal packages.

Thanks
Richard

WorMzy

Forum Moderator

From: Scotland

Registered: 2010-06-16

Posts: 11,863

Website

Re: Interrupt package uninstallation

Not as far as I know. Put your check before you call pacman -R.

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uiii

Member

Registered: 2009-02-25

Posts: 27

Re: Interrupt package uninstallation

Put your check before you call pacman -R.

That is the point, I need to prevent pacman to uninstall the package, because my custom wrapper application should be used. So I can't put check before pacman is used.

Last edited by uiii (2016-05-05 08:45:19)

WorMzy

Forum Moderator

From: Scotland

Registered: 2010-06-16

Posts: 11,863

Website

Re: Interrupt package uninstallation

I don't understand. If you don't want pacman to remove a package, don't tell pacman to remove the package.

The only reason I can think of that pacman would abort during a package removal (and not at the start of a transaction) would be if the filesystem became read-only.

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Sakura:-
Mobo: MSI MAG X570S TORPEDO MAX // Processor: AMD Ryzen 9 5950X @4.9GHz // GFX: AMD Radeon RX 5700 XT // RAM: 32GB (4x 8GB) Corsair DDR4 (@ 3000MHz) // Storage: 1x 3TB HDD, 6x 1TB SSD, 2x 120GB SSD, 1x 275GB M2 SSD

Making lemonade from lemons since 2015.

uiii

Member

Registered: 2009-02-25

Posts: 27

Re: Interrupt package uninstallation

If you don't want pacman to remove a package, don't tell pacman to remove the package.

I don't want to use it, it's for cases when I accidentally use pacman to remove the package. And now it is only for my personal use, but later, maybe, I will make it public.

The only reason I can think of that pacman would abort during a package removal (and not at the start of a transaction) would be if the filesystem became read-only.

I've tried something similar - kill the pacman process, but it leaves a lock file in the filesystem so I have to remove it after. I think that making the filesystem read-only (actually I don't event know how to do it on running system) will result to the same.

Last edited by uiii (2016-05-05 09:26:18)

Lone_Wolf

Forum Moderator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 11,922

Re: Interrupt package uninstallation

uiii, this looks like you could solve it with a pacman hook ( man alpm-hooks ) .

the hook would look something like this:

[Trigger]
Type = Package
Operation = Remove
Target = special_package1
Target = special_package2
Target = special_package3


[Action]
Description = Backup some stuff BEFORE removal
When = PreTransaction
Exec = /usr/bin/my_special_backup.sh
AbortOnFail
# if backup is not succesfull, my_special_backup.sh should return non-zero, causing the removal to abort

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(A works at time B)  && (time C > time B ) ≠  (A works at time C)

Ropid

Member

Registered: 2015-03-09

Posts: 1,069

Re: Interrupt package uninstallation

There is a setting "HoldPkg = ..." in /etc/pacman.conf. The man-page says this about it:

"If a user tries to --remove a package that’s listed in HoldPkg, pacman will ask for confirmation before proceeding. Shell-style glob patterns are allowed."