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C

Bind and Listen on an Available Port in a Range

See more Socket/SSL/TLS Examples

Demonstrates Socket.BindAndListenPortRange, which searches an inclusive port range for an available TCP port, binds it, and begins listening. It returns the selected port, or -1 on failure.

Background. This is useful when any of several ports is acceptable and the application needs to discover which one was bound.

Chilkat C Downloads

C
#include <C_CkSocket.h>

void ChilkatSample(void)
    {
    HCkSocket socket;
    int boundPort;

    socket = CkSocket_Create();

    //  Search the inclusive port range for an available TCP port, bind it, and begin listening.  The
    //  method returns the selected port, or -1 when no port can be bound.
    boundPort = CkSocket_BindAndListenPortRange(socket,5000,5100,25);
    if (boundPort < 0) {
        printf("%s\n",CkSocket_lastErrorText(socket));
        CkSocket_Dispose(socket);
        return;
    }

    printf("Listening on port %d\n",boundPort);


    CkSocket_Dispose(socket);

    }