stdin set to nonblocking mode

[Simon Marlow]

On 11 August 2005 01:18, John Meacham wrote:

> Why do we set file descriptors to nonblocking mode anyway if they are
> waited on by a select. there shouldn't be a need to use both

It avoids an extra system call per read(), i.e. a single read() instead
of select() + read().  And there's a slight chance of a race between the
select() and read() calls, if some other thread or process is reading
from the same descriptor.  With non-blocking read(), this isn't an
issue.

The overhead of the extra syscall is probably a non-issue, but the race
is mildly worrying.

Cheers,
	Simon