(Unicode C) Multiple SendReqExec on Same Connection

Shows how to execute a series of commands on an SSH server and retrieve each command's output (using SendReqExec). Each call to SendReqExec requires its own logical channel. This is not a separate SSH connection -- it's simply a new session channel on the existing SSH connection.

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#include <C_CkSshW.h>

void ChilkatSample(void)
    {
    HCkSshW ssh;
    const wchar_t *hostname;
    int port;
    BOOL success;
    int channelNum;
    const wchar_t *cmd;
    int pollTimeoutMs;
    int n;
    const wchar_t *cmdOutput;

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    ssh = CkSshW_Create();

    // Hostname may be an IP address or domain:
    hostname = L"172.16.16.46";
    port = 22;

    success = CkSshW_Connect(ssh,hostname,port);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // If receiving output from a command stalls for more than 5 seconds, then stop waiting.
    CkSshW_putIdleTimeoutMs(ssh,5000);

    // Authenticate using login/password:
    success = CkSshW_AuthenticatePw(ssh,L"myLogin",L"myPassword");
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // Open a session channel.  (It is possible to have multiple
    // session channels open simultaneously.)
    channelNum = CkSshW_OpenSessionChannel(ssh);
    if (channelNum < 0) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // Request a directory listing on the remote server:
    // If your server is Linux/UNIX, change the string from "dir" to "ls"
    // Note: Some SSH servers require a CRLF instead of a bare-LF
    cmd = L"ls -al\n";
    success = CkSshW_SendReqExec(ssh,channelNum,cmd);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // Read whatever output may already be available on the
    // SSH connection.  ChannelReadAndPoll returns the number of bytes
    // that are available in the channel's internal buffer that
    // are ready to be "picked up" by calling GetReceivedText
    // or GetReceivedData.
    // A return value of -1 indicates failure.
    // A return value of -2 indicates a failure via timeout.

    // The ChannelReadAndPoll method waits
    // for data to arrive on the connection usingi the IdleTimeoutMs
    // property setting.  Once the first data arrives, it continues
    // reading but instead uses the pollTimeoutMs passed in the 2nd argument:
    // A return value of -2 indicates a timeout where no data is received.
    pollTimeoutMs = 2000;
    n = CkSshW_ChannelReadAndPoll(ssh,channelNum,pollTimeoutMs);
    if (n < 0) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // Close the channel:
    success = CkSshW_ChannelSendClose(ssh,channelNum);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // Perhaps we did not receive all of the commands output.
    // To make sure,  call ChannelReceiveToClose to accumulate any remaining
    // output until the server's corresponding "channel close" is received.
    success = CkSshW_ChannelReceiveToClose(ssh,channelNum);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // Get the accumulated output of the command:

    cmdOutput = CkSshW_getReceivedText(ssh,channelNum,L"ansi");
    if (CkSshW_getLastMethodSuccess(ssh) == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    // Display the remote shell's command output:
    wprintf(L"%s\n",cmdOutput);
    wprintf(L"----\n");

    // -----------------------------------------------------------------
    // Now for the 2nd SendReqExe (on the same connection,
    // but on a separate logical channel).
    // -----------------------------------------------------------------

    channelNum = CkSshW_OpenSessionChannel(ssh);
    if (channelNum < 0) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    cmd = L"nslookup chilkatsoft.com\n";
    success = CkSshW_SendReqExec(ssh,channelNum,cmd);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    pollTimeoutMs = 2000;
    n = CkSshW_ChannelReadAndPoll(ssh,channelNum,pollTimeoutMs);
    if (n < 0) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    success = CkSshW_ChannelSendClose(ssh,channelNum);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    success = CkSshW_ChannelReceiveToClose(ssh,channelNum);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    cmdOutput = CkSshW_getReceivedText(ssh,channelNum,L"ansi");
    if (CkSshW_getLastMethodSuccess(ssh) == FALSE) {
        wprintf(L"%s\n",CkSshW_lastErrorText(ssh));
        CkSshW_Dispose(ssh);
        return;
    }

    wprintf(L"%s\n",cmdOutput);


    CkSshW_Dispose(ssh);

    }