Continue SFTP Keyboard-Interactive Authentication

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Demonstrates the Chilkat SFtp.ContinueKeyboardAuth method, which submits a response to a keyboard-interactive prompt. The only argument is the response text; for a request with multiple prompts, an XML response is supplied instead. It returns XML indicating the next prompt or the final result.

Background: This is the second half of the exchange started by StartKeyboardAuth. A server may issue several rounds of prompts, so a robust client loops: submit answers, read the returned XML, and continue until it sees success or failure. On success, remember that InitializeSftp still must be called before any file operation.

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#include <C_CkSFtp.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSFtp sftp;
    int port;
    const char *infoRequestXml;
    const char *password;
    const char *result;

    success = FALSE;

    //  Demonstrates the SFtp.ContinueKeyboardAuth method, which submits a response to a
    //  keyboard-interactive prompt.  The only argument is the response.  For multiple prompts, an
    //  XML response is supplied instead.

    sftp = CkSFtp_Create();

    //  Step 1: Connect the SSH transport.  Port 22 is the usual port.
    port = 22;
    success = CkSFtp_Connect(sftp,"sftp.example.com",port);
    if (success == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSFtp_Dispose(sftp);
        return;
    }

    //  Begin keyboard-interactive authentication to receive the server's prompt(s).
    infoRequestXml = CkSFtp_startKeyboardAuth(sftp,"mySshLogin");
    if (CkSFtp_getLastMethodSuccess(sftp) == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSFtp_Dispose(sftp);
        return;
    }

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    password = "mySshPassword";

    //  Submit the response (typically the password).  The returned XML indicates the next prompt or
    //  the final result.
    result = CkSFtp_continueKeyboardAuth(sftp,password);
    if (CkSFtp_getLastMethodSuccess(sftp) == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSFtp_Dispose(sftp);
        return;
    }

    printf("%s\n",result);

    //  On success, initialize the SFTP subsystem.
    success = CkSFtp_InitializeSftp(sftp);
    if (success == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSFtp_Dispose(sftp);
        return;
    }

    CkSFtp_Disconnect(sftp);


    CkSFtp_Dispose(sftp);

    }