[arch-general] pacman caches packages with u=rw, g=, o= permissions

[u34 at net9.ga]

mpan via arch-general <arch-general at lists.archlinux.org> wrote:

> > According to
> > https://wiki.archlinux.org/title/System_maintenance#Partial_upgrades_are_unsupported
> > pacman -Sywu is not safe. But pacman -Syu is safe. Quoting the wiki, the
> > rational is that pacman -Sywu
> >      will update the pacman sync database without installing the newer packages.
> > What I fail to see is why pacman -Sywu, followed by pacman -Su,
> > 1. Will update the pacman sync database without installing the newer packages.
> > But then
> > 2. Will not update the pacman sync database while installing the
> >     packages it has prevoiusly downloaded.
>    If `-Sywu` is *immediately* followed by `-Su` then there is no risk 
> of running into a partial upgrade, but:
> 
>   1) Then there is normally no reason to run those as separate commands,
>      as `-Sywu` immediately followed by `-Su` has no benefits compared
>      to simple `-Syu`. `-Sywu` is used to avoid the update, but download
>      package files to the cache.
>   2) You are mentioning a system timer, so I assume `-Sywu` is not
>      immediately followed by `-Su`. Unless you are also running
>      unattended updates, which is even worse and *will* eventually
>      break your system.
> 
>    `checkupdates -d` does exactly the same as `-Sywu`, but without 
> updating the system-wide sync databases. So pacman???s view of everything 
> remains the same as if nothing was updated. It only gets package files 
> in the cache.

I have tried to look into the checkupdates script, but got confused. It 
looks not long bash script. Does it do the work by copying the system-wide 
sync databases to a temporary databases, works on those temporary databases, 
and wiped them before exiting?

--
jadon