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Re: select()


Todd M. Grimm said:
> 
> I am using select() to test whether there are bytes on a socket to read 
> without blocking my program to check on this.
> 
> The problem is that even when there is no data it returns a 1 to say that 
> there is data. This causes my program to try a read which blocks because 
> there really is no data.
> 
> I saw several messages in the archives of this list about this, but all I 
> could find were questions. No one ever seemed to answer the question.
> 
> Please let me know if you know how to get select() to work right or if 
> there is a nother way to test for bytes without blocking.

  Without seeing the code it is impossible to judge what is
happening, but in general, select returns whether a socket is
*ready*, not just readable.  For example, if the other end has
closed the connection select() will return that the socket is
ready.  A read on the socket will return 0 to indicate the
close.

  Regards,
      Harry.
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