(MFC) Wait for Async Method to Complete

Demonstrates using the Wait method to wait for an asynchronous method to complete. This example will do an SFTP upload (over SSH) and will use the Async version of each method. Obviously, waiting for the async method to complete is the same as making a synchronous call, but an application wouldn't typically do this. An application might, for example, do other things as a background task is running, and then later wait for the task to complete.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkGlobal.h>
#include <CkSFtp.h>
#include <CkTask.h>

void ChilkatSample(void)
    {
    CkString strOut;

    // All Chilkat classes can be unlocked at once at the beginning of a program
    // by calling UnlockBundle.  It requires a Bundle unlock code.
    CkGlobal chilkatGlob;
    bool success = chilkatGlob.UnlockBundle("Anything for 30-day trial.");
    if (success != true) {
        strOut.append(chilkatGlob.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkSFtp sftp;

    // Set some timeouts, in milliseconds:
    sftp.put_ConnectTimeoutMs(15000);
    sftp.put_IdleTimeoutMs(15000);
    int waitMaxMs = 30000;

    // Connect to the SSH server.  
    // The standard SSH port = 22
    // The hostname may be a hostname or IP address.
    int port = 22;
    const char *hostname = "www.my-ssh-server.com";

    CkTask *task = sftp.ConnectAsync(hostname,port);
    if (sftp.get_LastMethodSuccess() == false) {
        strOut.append(sftp.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Start the background task.
    success = task->Run();
    if (!success) {
        strOut.append(task->lastErrorText());
        strOut.append("\r\n");
    }

    // Wait for the connect task to finish.
    // The true/false returned by Wait applies to the Wait method call, not the task.
    success = task->Wait(waitMaxMs);
    if (!success || (task->get_StatusInt() != 7) || (task->get_TaskSuccess() != true)) {
        if (!success) {
            // The task.LastErrorText applies to the Wait method call.
            strOut.append(task->lastErrorText());
            strOut.append("\r\n");
        }
        else {
            // The ResultErrorText applies to the underlying task method call (i.e. the Connect)
            strOut.append(task->status());
            strOut.append("\r\n");
            strOut.append(task->resultErrorText());
            strOut.append("\r\n");
        }

        delete task;
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    delete task;

    // Authenticate with the SSH server.  Chilkat SFTP supports
    // both password-based authenication as well as public-key
    // authentication.  This example uses password authenication.
    task = sftp.AuthenticatePwAsync("myLogin","myPassword");
    // To keep the example short, we'll skip handling failures.
    // The failures would be handled in the same way as shown above.

    success = task->Run();
    success = task->Wait(waitMaxMs);
    delete task;

    // After authenticating, the SFTP subsystem must be initialized:
    task = sftp.InitializeSftpAsync();
    success = task->Run();
    success = task->Wait(waitMaxMs);
    delete task;

    // Upload from the local file to the SSH server.
    // Important -- the remote filepath is the 1st argument,
    // the local filepath is the 2nd argument;
    const char *remoteFilePath = "hamlet.xml";
    const char *localFilePath = "c:/temp/hamlet.xml";

    task = sftp.UploadFileByNameAsync(remoteFilePath,localFilePath);
    if (sftp.get_LastMethodSuccess() == false) {
        strOut.append(sftp.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    success = task->Run();
    success = task->Wait(waitMaxMs);
    if (!success || (task->get_StatusInt() != 7) || (task->get_TaskSuccess() != true)) {
        if (!success) {
            // The task.LastErrorText applies to the Wait method call.
            strOut.append(task->lastErrorText());
            strOut.append("\r\n");
        }
        else {
            // The ResultErrorText applies to the underlying task method call (i.e. the Connect)
            strOut.append(task->status());
            strOut.append("\r\n");
            strOut.append(task->resultErrorText());
            strOut.append("\r\n");
        }

        delete task;
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    delete task;
    strOut.append("File uploaded.");
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }