Android™

Read the Target of a Symbolic Link

Demonstrates the Chilkat SFtp.ReadLink method, which returns the target path stored in a remote symbolic link. The only argument is the link path. The example then resolves the target to an absolute path with RealPath.

Background: ReadLink returns the raw string stored in the link exactly as it was created — which may be relative, absolute, or even dangling — without resolving it. That distinction matters: to learn where a link actually leads you follow it with RealPath, which canonicalizes the path on the server. Reading the raw target is the right choice when you need to inspect or preserve the link itself rather than its destination.

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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;

    //  Demonstrates the SFtp.ReadLink method, which returns the target path stored in a remote
    //  symbolic link.  The only argument is the link path.

    CkSFtp sftp = new CkSFtp();

    //  Connect, authenticate, and initialize the SFTP subsystem.
    int port = 22;
    success = sftp.Connect("sftp.example.com",port);
    if (success == false) {
        Log.i(TAG, sftp.lastErrorText());
        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.
    String password = "mySshPassword";

    success = sftp.AuthenticatePw("mySshLogin",password);
    if (success == false) {
        Log.i(TAG, sftp.lastErrorText());
        return;
        }

    success = sftp.InitializeSftp();
    if (success == false) {
        Log.i(TAG, sftp.lastErrorText());
        return;
        }

    //  Read the target of a symbolic link.  The returned value is the raw target string stored in
    //  the link; it is not canonicalized and can be relative or absolute.
    String target = sftp.readLink("subdir/latest.log");
    if (sftp.get_LastMethodSuccess() == false) {
        Log.i(TAG, sftp.lastErrorText());
        return;
        }

    Log.i(TAG, "The link points to: " + target);

    //  To resolve it to an absolute path, pass it to RealPath.
    String absTarget = sftp.realPath(target,"");
    if (sftp.get_LastMethodSuccess() == false) {
        Log.i(TAG, sftp.lastErrorText());
        return;
        }

    Log.i(TAG, "Absolute target: " + absTarget);

    sftp.Disconnect();

  }

  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."
  }
}