Re: [gentoo-user] New profile 17: How urgent is the rebuild of world technically?

[Heiko Baums <lists@baums-on-web.de>]

Am Sun, 3 Dec 2017 04:45:59 +0100
schrieb tuxic@posteo.de:

> Suppose one would do an emerge @world...and then BOOOM! a powerfailyre
> would stop the whole thing.

In such a case you should consider buying a UPS.

Can't you do this over night or a weekend? And how often do you have a
power failure?

> Further suppose the filesystem, the
> hardware and anything has survived luckily -- only emerge @world needs
> to be restarted.
> And one does NOT an emerge --resume but an emerge @world.

If I'm not mistaken in this case an `emerge --resume` should be
the right thing. It usually resumes the last interrupted emerge command.

That is if you run `emerge -e @world` press Ctrl-C `emerge --resume`
should resume this previous started `emerge -e @world` including the
package which was built when it was interrupted. Ctrl-C is principally
the same as a power failure.

If this fails for some reason then you'd have to rerun the whole
`emerge -e @world` I guess.

> In this particular case...how does emerge knows from the previous
> emerge @world what packages has been recompiled already and are "PIE"?

Like I said before. emerge always calculates the dependency tree, which
is a lot faster in case of `emerge -e @world` than in case of `emerge
-uDN @world`. And then it knows which packages have already been
installed and which are not.

That said I haven't run an `emerge -e @world` before. So I'm actually
not sure if this works the same way as with an `emerge -uDN @world`.

Heiko