[gccsdk] Unixlib select bug?

Not sure if this is the right place to post this..

I think there is a bug in the select() timeout logic - the effect is it
seems to ignore the tv_usec part of the timeout. Python's time.sleep
used select to do the actual waiting, and it was found that it just
ignored the fractional part, so sleep(0.2) would just return. In fact
sleep (0.99) also just returns, sleep (1.0) sleeps for a second,
sleep(1.99) also sleeps for a second..

I had a look at the logic in ul_select.c and it appears to use this to
work out then end time..

          end = now + timeout->tv_sec * 100
            + (50000 + timeout->tv_usec) / 1000000;

However, the tv_usec part will just get end up as 0 (unless its >
1000000, but that will get rejected by the earlier check). I think the
problem is it's converting usec to seconds, rather than usec to
centiseconds, so it should be:

          end = now + timeout->tv_sec * 100
            + (500 + timeout->tv_usec) / 10000;

In fact:

          end = now + timeout->tv_sec * 100 + timeout->tv_usec / 10000;

Might be enough.

Cheers,

Chris

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