Avoiding sleep in V3 testsuite

[Paolo Carlini]

Hi,

>Here's a sketch of how I'm proposing to fix this.  (I'll figure out a
>better way to define _GLIBCXX_SYSV_SEM.)  Any objections?
>  
>
First blush, certainly not from me.

>(Actually, come to think of it, I can't see any reason that we need
>synchronization at all in this test -- except maybe that we're using
>"exit" -- rather than "_exit" -- to leave the child, which seems
>confused in and of itself.  Since this test uses fifos, we can safely
>assume that _exit exists.  So, I guess to fix 9507.cc, in particular,
>it would suffice just to remove the sleep calls.)
>  
>
Actually, as probably you already noticed, I'm guilty of adding those sleep
to that testcase: after the previous commit, changing the openmore, I saw
intermittent failures on some archs, and tried quickly fixing the problem
following our usual rough sleep-based strategy... In case you eventually
decide to only remove completely the sleeps in this case, please make sure
to regtest on many archs.

Thanks!
Paolo.