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C

SSH Parallel Remote Commands on Multiple Servers

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Shows how to execute a command in parallel on multiple servers.

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C
#include <C_CkSsh.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSsh ssh1;
    HCkSsh ssh2;
    HCkSsh ssh3;
    int port;
    const char *cmd;
    int ssh1Channel;
    int ssh2Channel;
    int ssh3Channel;
    int pollTimeoutMs;
    int numFinished;
    int channel;
    BOOL ssh1Finished;
    BOOL ssh2Finished;
    BOOL ssh3Finished;

    success = FALSE;

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

    // Executing a command on multiple servers simultaneously is straightforward.
    // It's just a matter of using one SSH object per server..
    ssh1 = CkSsh_Create();
    ssh2 = CkSsh_Create();
    ssh3 = CkSsh_Create();

    port = 22;
    success = CkSsh_Connect(ssh1,"ssh-server1.com",port);
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh1));
        CkSsh_Dispose(ssh1);
        CkSsh_Dispose(ssh2);
        CkSsh_Dispose(ssh3);
        return;
    }

    // Authenticate using login/password:
    success = CkSsh_AuthenticatePw(ssh1,"sshLogin1","sshPassword1");
    if (success != TRUE) {
        printf("%s\n",CkSsh_lastErrorText(ssh1));
        CkSsh_Dispose(ssh1);
        CkSsh_Dispose(ssh2);
        CkSsh_Dispose(ssh3);
        return;
    }

    // Connect and authenticate with 2 more servers.
    // For brevity, the success/failure won't be checked...
    success = CkSsh_Connect(ssh2,"ssh-server2.com",port);
    success = CkSsh_AuthenticatePw(ssh2,"sshLogin2","sshPassword2");
    success = CkSsh_Connect(ssh3,"ssh-server3.com",port);
    success = CkSsh_AuthenticatePw(ssh3,"sshLogin3","sshPassword3");

    // Note: If we wanted, we could've used ConnectAsync and AuthenticatePwAsync
    // to do the connecting and authenticating in parallel...

    // The command to be run on each SSH server will sleep for 5 seconds,
    // and then show the current system date/time.
    cmd = "sleep 5; date";

    // Start each command
    ssh1Channel = CkSsh_QuickCmdSend(ssh1,cmd);
    if (ssh1Channel < 0) {
        printf("%s\n",CkSsh_lastErrorText(ssh1));
        CkSsh_Dispose(ssh1);
        CkSsh_Dispose(ssh2);
        CkSsh_Dispose(ssh3);
        return;
    }

    // For brevity, we're not checking the return values here:
    ssh2Channel = CkSsh_QuickCmdSend(ssh2,cmd);
    ssh3Channel = CkSsh_QuickCmdSend(ssh3,cmd);

    // OK, at this point the command is running simultaneously on each server.

    // Now collect the results of each command.
    pollTimeoutMs = 50;
    numFinished = 0;

    // Note: You would rewrite this code to use arrays.
    ssh1Finished = FALSE;
    ssh2Finished = FALSE;
    ssh3Finished = FALSE;
    while (numFinished < 3) {
        // Check to see if anything has finished.
        // QuickCmdCheck returns -1 if there are no errors and nothing else finished
        // QuickCmdCheck returns -2 if there was an error (such as a lost connection)
        // QuickCmdCheck returns a channel number if a channel finished.
        if (ssh1Finished != TRUE) {
            channel = CkSsh_QuickCmdCheck(ssh1,pollTimeoutMs);
            if (channel == -2) {
                printf("%s\n",CkSsh_lastErrorText(ssh1));
                CkSsh_Dispose(ssh1);
                CkSsh_Dispose(ssh2);
                CkSsh_Dispose(ssh3);
                return;
            }

            if (channel == ssh1Channel) {
                printf("---- ssh1 channel %d finished ----\n",channel);
                printf("%s\n",CkSsh_getReceivedText(ssh1,channel,"ansi"));
                numFinished = numFinished + 1;
                ssh1Finished = TRUE;
            }

        }

        if (ssh2Finished != TRUE) {
            channel = CkSsh_QuickCmdCheck(ssh2,pollTimeoutMs);
            if (channel == -2) {
                printf("%s\n",CkSsh_lastErrorText(ssh2));
                CkSsh_Dispose(ssh1);
                CkSsh_Dispose(ssh2);
                CkSsh_Dispose(ssh3);
                return;
            }

            if (channel == ssh2Channel) {
                printf("---- ssh2 channel %d finished ----\n",channel);
                printf("%s\n",CkSsh_getReceivedText(ssh2,channel,"ansi"));
                numFinished = numFinished + 1;
                ssh2Finished = TRUE;
            }

        }

        if (ssh3Finished != TRUE) {
            channel = CkSsh_QuickCmdCheck(ssh3,pollTimeoutMs);
            if (channel == -2) {
                printf("%s\n",CkSsh_lastErrorText(ssh3));
                CkSsh_Dispose(ssh1);
                CkSsh_Dispose(ssh2);
                CkSsh_Dispose(ssh3);
                return;
            }

            if (channel == ssh3Channel) {
                printf("---- ssh3 channel %d finished ----\n",channel);
                printf("%s\n",CkSsh_getReceivedText(ssh3,channel,"ansi"));
                numFinished = numFinished + 1;
                ssh3Finished = TRUE;
            }

        }

    }

    // --------------
    // Sample output:

    // 	---- ssh2 channel 101 finished ----
    // 	Fri Dec 23 00:25:48 UTC 2016
    // 
    // 	---- ssh3 channel 102 finished ----
    // 	Thu Dec 22 18:25:12 CST 2016
    // 
    // 	---- ssh1 channel 100 finished ----
    // 	Thu Dec 22 18:25:48 CST 2016


    CkSsh_Dispose(ssh1);
    CkSsh_Dispose(ssh2);
    CkSsh_Dispose(ssh3);

    }