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Re: printf before main?
On Tue, Mar 23, 2010 at 3:20 PM, Brendan Miller <catphive@catphive.net> wrote:
> Is it safe to call printf family functions, or other streams
> functionality before main? In other words, in global C++ constructors,
> or functions with __attribute__((constructor))?
>
> I'm wondering if any buffers for standard output are being allocated
> during that phase... I need to do some output potentially before main
> for logging purposes, and I'm wondering if I'd better off calling
> write directly.
>
> Brendan
>
Printf is _very_ heavyweight. You should call write directly since
you probably don't need all of the formatting options provided by
printf.
Ryan S. Arnold