You cannot send to a socket whilst the same end that you are trying to send to is in a receive state. Even if the receive is being done on a dup() of the socket in a fork or thread.

Most of the time, that isn't a problem because comms protocols tend to be a conversation where one end speaks and the other replies. If you need to be able to initiate sends from both ends, then your reads will need to be non-blocking.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
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In reply to Re: Bidirectional Socket, Blocking by BrowserUk
in thread Bidirectional Socket, Blocking by DanielPHuber

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