[libvirt] [PATCH 3/3] virCommand: use procfs to learn opened FDs

[Florian Weimer]

* Eric Blake:

> On 7/14/19 12:23 AM, Florian Weimer wrote:
>> * Eric Blake:
>> 
>>> Does anyone know if glibc guarantees that opendir/readdir in between
>>> multi-threaded fork() and exec() is safe, even though POSIX does not
>>> guarantee that safety in general?
>> 
>> glibc supports malloc after multi-threaded fork as an extension (or as
>> a bug, because it makes malloc not async-signal-safe).
>
> It's not a bug for glibc to provide guarantees above what POSIX
> requires, but IS a bug for applications to depend on those guarantees
> without realizing they are non-portable.

It's a bug because it makes malloc not async-signal-safe (as required by
POSIX) in our current implementation of malloc.