Re: Why does close_stdout close stdout and stderr?

[Florian Weimer]

* Kamil Dudka:

> On Friday, May 10, 2019 12:17:11 AM CEST Paul Eggert wrote:
>> On 5/8/19 11:39 PM, Florian Weimer wrote:
>> > atexit handlers run before ELF destructors (and some C++ destructors).
>> > There can also be multiple such handlers.  So it's not true that an
>> > atexit handler always runs last.
>> 
>> OK, but this shouldn't be a problem with any applications currently
>> using close_stdout. At least, none of the applications I know about.
>
> How would you know if they did?
>
> As long as you link libraries dynamically, any of the directly or indirectly 
> linked libraries can introduce an ELF destructor or atexit() handler anytime, 
> which would take an immediate effect even on your already built applications.
> People also like to use instrumentation libraries enforced by LD_PRELOAD in 
> their test environment.  Those can easily clash with such cleanup handlers.

Right.  And I found close_stdout after someone reported problems with an
LD_PRELOAD-like mechanism and its logging output.  For some users, this
is an actual problem.

Thanks,
Florian