I've noticed that my C++ application stops printing to stdout after a 
while, and I didn't know why. It turns out that printing via 
'std::ostream::operator<<' will eventually call '__stdio_write()', which 
then calls 'writev()'. But, if 'writev()' is interrupted by a signal and 
SA_RESTART is not set, then it will return EINTR, which will cause both 
the 'FILE' structure and the corresponding C++ stream to be marked bad. 
I think the current behavior is very confusing, so attached is a patch 
to retry on EINTR.

Thanks,

Dominic