Re: Building many packages in order

[Hartmut Goebel <h.goebel@crazy-compilers.com>]

Am 21.10.2016 um 13:53 schrieb Efraim Flashner:
> If you want to build all packages that are python- or python2-, then you
> can call 'guix build $(guix package -A ^python | cut -f1)'

I was about to answer that this will not work if the length of the
arguments string exceeds some limit. This made me re-check my premises
and found they are wrong: Both the length of the commands line and the
number of arguments to be passed to a new process are *really* big. See [1].

So I checked again and my command line is about 18,000 characters long
and even xargs calls `guix build` only once.

So my premises was irrelevant and my "mass rebuild" script works as
expected.

> If you want all the packages that rely on python or python-2, then you
> can call 'guix build $(guix refresh -l python python@2 | cut -d':' -f2)'

Thanks for this trick. I'm not used to "guix refresh" and my code for
selecting the packages is much more complicated. (I select them by
name.) I really have to get more common with these guix subcommands.


[1]
http://unix.stackexchange.com/questions/120642/what-defines-the-maximum-size-for-a-command-single-argument

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | h.goebel@crazy-compilers.com               |
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