Android™

Active and Passive Modes in FTP

See more FTP Examples

The Passive property controls whether data connections for uploads/downloads are established in Active or Passive mode. To use Active mode, set the Passive property = _FALSE_. This is the default. To use Passive mode, set the Passive property = _TRUE_.

About Passive/Active Modes:

Active Mode:
The FTP client chooses a port number and sends a “PORT” command to the FTP server. The FTP client then listens at the chosen port and the FTP server issues a connect request to establish the connection. The data connection is outgoing from the FTP server, and incoming to the FTP client.

Passive Mode:
The FTP client sends a PASV command to the FTP server. The FTP server chooses a port number and sends it in the PASV response. The FTP server then listens at that port for the incoming connect request from the FTP client. The data connection is incoming to the FTP server, and outgoing from the FTP client.

Android™

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    boolean success = false;

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

    CkFtp2 ftp = new CkFtp2();

    ftp.put_Hostname("ftp.something.com");
    ftp.put_Username("test");
    ftp.put_Password("test");

    // Connect and login to the FTP server.
    success = ftp.Connect();
    if (success != true) {
        Log.i(TAG, ftp.lastErrorText());
        return;
        }

    // To use Passive mode:
    ftp.put_Passive(true);

    // or...
    // To use Active mode:
    ftp.put_Passive(false);

    // ..

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}