Delphi ActiveX

Close a Remote SFTP File or Directory Handle

Demonstrates the Chilkat SFtp.CloseHandle method, which closes a remote file or directory handle previously returned by OpenFile or OpenDir. The only argument is the handle.

Background: Every opened handle corresponds to state the server holds, and servers cap how many a session may keep open at once, so a long-running program that forgets to close handles will eventually start failing to open new ones. Closing also ensures buffered writes are committed. Once closed, a handle is invalid and must not be reused.

Chilkat Delphi ActiveX Downloads

Download Chilkat for Delphi ActiveX

Delphi ActiveX

var
success: Integer;
sftp: TChilkatSFtp;
port: Integer;
password: WideString;
handle: WideString;

begin
success := 0;

//  Demonstrates the SFtp.CloseHandle method, which closes a remote file or directory handle.  The
//  only argument is the handle returned by OpenFile or OpenDir.

sftp := TChilkatSFtp.Create(Self);

//  Connect, authenticate, and initialize the SFTP subsystem.
port := 22;
success := sftp.Connect('sftp.example.com',port);
if (success = 0) then
  begin
    Memo1.Lines.Add(sftp.LastErrorText);
    Exit;
  end;

//  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.
password := 'mySshPassword';

success := sftp.AuthenticatePw('mySshLogin',password);
if (success = 0) then
  begin
    Memo1.Lines.Add(sftp.LastErrorText);
    Exit;
  end;

success := sftp.InitializeSftp();
if (success = 0) then
  begin
    Memo1.Lines.Add(sftp.LastErrorText);
    Exit;
  end;

//  Open a remote file, obtaining a handle.
handle := sftp.OpenFile('subdir/data.txt','readOnly','openExisting');
if (sftp.LastMethodSuccess = 0) then
  begin
    Memo1.Lines.Add(sftp.LastErrorText);
    Exit;
  end;

//  ... use the handle ...

//  Close the handle to release the server-side resource.  A handle should not be used after it
//  is closed.
success := sftp.CloseHandle(handle);
if (success = 0) then
  begin
    Memo1.Lines.Add(sftp.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add('Handle closed.');

sftp.Disconnect();