Delphi DLL

Open an SSH Session Channel

Demonstrates the Chilkat Ssh.OpenSessionChannel method, which opens a new SSH session channel. It takes no arguments and returns the channel number, or -1 on failure. The transport must already be connected and authenticated.

Background: SSH multiplexes independent channels over one authenticated connection, and a session channel is the one used to run a command, start a shell, or invoke a subsystem. Opening the channel is only the container — nothing runs until you follow it with an exec, shell, or subsystem request. Always test for a negative return rather than assuming success.

Chilkat Delphi DLL Downloads

Download Chilkat for Delphi DLL

Delphi DLL

var
success: Boolean;
ssh: HCkSsh;
sshPort: Integer;
password: PWideChar;
channelNum: Integer;

begin
success := False;

//  Demonstrates the Ssh.OpenSessionChannel method, which opens a new SSH session channel.  It
//  takes no arguments and returns the channel number, or -1 on failure.  The transport must
//  already be connected and authenticated.

ssh := CkSsh_Create();

sshPort := 22;
success := CkSsh_Connect(ssh,'ssh.example.com',sshPort);
if (success = False) then
  begin
    Memo1.Lines.Add(CkSsh__lastErrorText(ssh));
    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 := CkSsh_AuthenticatePw(ssh,'mySshLogin',password);
if (success = False) then
  begin
    Memo1.Lines.Add(CkSsh__lastErrorText(ssh));
    Exit;
  end;

//  Open a session channel.  A negative return value indicates failure.
channelNum := CkSsh_OpenSessionChannel(ssh);
if (channelNum < 0) then
  begin
    Memo1.Lines.Add(CkSsh__lastErrorText(ssh));
    Exit;
  end;

Memo1.Lines.Add('Opened session channel: ' + IntToStr(channelNum));

//  Opening the channel does not start a shell or command -- send an exec, shell, or subsystem
//  request next.

CkSsh_Disconnect(ssh);

CkSsh_Dispose(ssh);