On Thu, 28 Dec 2000 collver@softhome.net wrote:

> I noticed though that open("/dev/ttyXX", O_RDWR|O_NONBLOCK); made read()
> read nothing where open("/dev/dtyXX", O_RDWR); made read() read data.  Do
> you have an idea why?


I think that when O_NONBLOCK is set if there is no data to be read, read()
will return a -1 and set the value of errno to EAGAIN. This allows an
application to continue on with other tasks and can try to read again
later.

Brian

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| Brian Stark  Siemens Power Transmission & Distribution, Inc.          |
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