How to read environment variable in Glibc code

[Ángel González]

On 09/01/12 14:50, Carlos O'Donell wrote:
> The libc-help mailing list is the *correct* mailing list for this
> discussion, I'm removing the other mailing lists.
>
> The easiest way to achieve what you want is to provide your own
> version of printf in your program.
>
> This custom version of printf can be implemented in any way you want
> but works only for your program.
>
> If you want to stop output to stdio for precompiled programs then you
> need to rebuild libc with the appropriate change to printf.c.
>
> What problem are you having?
He may be having issues to call the real printf after he alias it with 
his version.

The non-standard RTLD_NEXT is very handy for that (man 3 dlsym).