Pascal (Lazarus/Delphi)

End a POP3 Session Without Committing Deletions

Demonstrates the Chilkat MailMan.Pop3EndSessionNoQuit method, which closes the POP3 connection without sending the QUIT command. Pending deletion marks are not committed — messages marked with DELE during the session remain in the mailbox. This example marks a message for deletion and then abandons the session so the deletion does not take effect.

Background: POP3's deferred-deletion model effectively gives you a transaction: marks made with DELE are only applied when the session ends with QUIT. Ending without QUIT is therefore a rollback — useful if an error occurs mid-processing and you'd rather leave the mailbox untouched than risk deleting messages you failed to handle. Use Pop3EndSession when you do want the deletions committed.

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Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.MailMan;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  mailman: TMailMan;

begin
  success := False;

  //  Demonstrates the MailMan.Pop3EndSessionNoQuit method, which closes the POP3 connection
  //  WITHOUT sending the QUIT command.  Pending deletion marks are not committed -- messages
  //  marked with DELE during the session remain in the mailbox.

  mailman := TMailMan.Create;

  //  Configure the POP3 server connection.
  mailman.MailHost := 'pop.example.com';
  mailman.MailPort := 995;
  mailman.PopSsl := True;
  mailman.PopUsername := 'user@example.com';
  mailman.PopPassword := 'myPassword';

  success := mailman.Pop3BeginSession();
  if (success = False) then
    begin
      WriteLn(mailman.LastErrorText);
      Exit;
    end;

  //  Mark a message for deletion...
  success := mailman.DeleteByMsgnum(1);
  if (success = False) then
    begin
      WriteLn(mailman.LastErrorText);
      Exit;
    end;

  //  ...but end the session without QUIT, so the deletion is NOT committed and the message
  //  remains in the mailbox.
  success := mailman.Pop3EndSessionNoQuit();
  if (success = False) then
    begin
      WriteLn(mailman.LastErrorText);
      Exit;
    end;

  WriteLn('Session closed without committing the pending deletion.');


  mailman.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.