Re: select() - Linux vs. BSD

[Mike Castle <dalgoda@ix.netcom.com>]

On Tue, May 29, 2001 at 11:55:24AM -0400, John Chris Wren wrote:
> select will not be altered.  In Linux, which claims BSD compliancy for this
> in the man page (but does not state either way what will happen to the
> bits), zeros the users bit masks when a timeout occurs.  I have written a

Where in the man page does it state this?  I just read it and couldn't find
any such statement.

I do, however, find the following:

       exceptfds will be watched for exceptions.   On  exit,  the
       sets  are  modified in place to indicate which descriptors
       actually changed status.


If there is a time out, it makes sense that no descriptors changed state,
and so everything would be zeroed out.

And actually, the example seems to support this:

           if (retval)
               printf("Data is available now.\n");
               /* FD_ISSET(0, &rfds) will be true. */

The comment seems to indicate that if retval is 0, then FD_ISSET will be
false.

mrc
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