LD_PRELOAD temporary patch

[Eygene Ryabinkin]

Jille, good day.

Tue, Dec 01, 2009 at 05:37:19PM +0100, Jille Timmermans wrote:
> Eygene Ryabinkin schreef:
> > If you're talking about rtld-elf local root, then the real issue
> > is that return values of unsetenv() are not checked and unsetenv()
> > could fail, thus leaving LD_PRELOAD and friends left unmodified.
> >
> Isn't the real issue that unsetenv() works differently from getenv()?
> If they both said 'your environment is crappy' there wouldn't have been
> a problem, would it?

You can't really rely on such behaviour: if you will, it will tie you to
the implementation details, because standards aren't defining such
interrelations (at least I can't find them: [1], [2], [3]).

I think that the rule is the following: if something can return/set
error value and you want to be sure that the call succeeded, you must
check that value and act accorgingly.

[1] http://www.opengroup.org/onlinepubs/000095399/functions/getenv.html
[2] http://www.opengroup.org/onlinepubs/000095399/functions/unsetenv.html
[3] http://www.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap08.html
-- 
Eygene
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