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C++

Wait for a Socket to Become Writable

See more Socket/SSL/TLS Examples

Demonstrates Socket.SelectForWriting, which waits for the socket, or sockets in a socket set, to become writable. It returns 1 if writable, 0 on timeout, or -1 on error.

Background. A timeoutMs of 0 performs a nonblocking poll. This is useful before attempting to send when the peer may be applying flow control.

Chilkat C++ Downloads

C++
#include <CkSocket.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkSocket socket;

    //  Connect to the server using TLS.
    bool bTls = true;
    int maxWaitMs = 5000;
    success = socket.Connect("example.com",5000,bTls,maxWaitMs);
    if (success == false) {
        std::cout << socket.lastErrorText() << "\r\n";
        return;
    }

    //  Wait up to 5 seconds for the socket (or sockets in a socket set) to become writable.  Returns 1 if
    //  writable, 0 on timeout, or -1 on error.
    int ready = socket.SelectForWriting(5000);
    if (ready < 0) {
        std::cout << socket.lastErrorText() << "\r\n";
        return;
    }

    if (ready != 1) {
        std::cout << "The socket did not become writable before the timeout." << "\r\n";
        return;
    }

    std::cout << "The socket is ready for writing." << "\r\n";
    }