Wait for data from recv()

This is a discussion on Wait for data from recv() within the Networking/Device Communication forums, part of the General Programming Boards category; Hello! Is there any way to make a program sleep until it has data from with a recv()? Many thanks...

  1. #1
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    Wait for data from recv()

    Hello!

    Is there any way to make a program sleep until it has data from with a recv()?

    Many thanks

  2. #2
    and the hat of int overfl Salem's Avatar
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    Without effort, recv() is blocking.
    So yes, your program is asleep in a recv() without data.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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  3. #3
    deletedforumuser
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    If you are trying to "unblock" accept() and recv()...you could just use



    Code:
    u_long* arg = 1; 
    
    ioctlsocket(thesocket, FIONBIO, &arg);

    Not sure if that's what you meant.

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    does blocking mean , so you block data from recv , send?

  5. #5
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    Blocking means that a system call "blocks" until some condition is satisfied. In the case of recv(), it means "wait until some data is available", and in send() it would mean "wait until the data has been sent".

    A non-blocking call is one that returns immediately, and you have to check some other way if some data was received or sent, or whatever it may be.

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