How to set a socket to non-blocking?

[Grant Edwards <grant.b.edwards@xxxxxxxxx>]

The eCos reference talks about how sockets behave when their marked as
non-blocking.  How does one set a socket to non-blocking?
The following fails with an "unsupported" error:

 fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);

-- 
Grant Edwards               grant.b.edwards        Yow! I guess you guys got
                                  at               BIG MUSCLES from doing too
                              gmail.com            much STUDYING!


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