TIdRemoteCMDClient is an ancestor to TIdRexec and TIdRSH.

TIdRemoteCMDClient = class(TIdTCPClient)

TIdRemoteCMDClient is an ancestor to TIdRexec and TIdRSH to accommodate some common properties and behaviors shared by those components. The behaviors shared include:

• The usage of a StdError port (TIdRemoteCMDClient.UseStdError)

• The server error handling is the same (TIdRemoteCMDClient.ErrorReply, TIdRemoteCMDClient.ErrorMessage)

• Command requests involve the same code except that the two parameters for authentication are different.

• Both protocols are used for executing commands on a remote server.

This is the error message that was returned from the Rexec or RSH Deamon.

property ErrorMessage: String;

This is the error message that was returned from the Rexec or RSH Deamon and this property is only if TIdRexec.Execute or TIRSH.Execute failed and TIdRemoteCMDClient.ErrorReply is True.

This indicates if the RSH or Rexec Deamons returned an error.

property ErrorReply: Boolean;

This indicates if the RSH or Rexec Deamons returned an error. The error can be obtained with the TIdRemoteCMDClient.ErrorMessage.

This property indicates if TIdRexec or TIdRSH should use a StdError port with the server.

property UseStdError: Boolean;

This property indicates if TIdRexec or TIdRSH should use a StdError port with the server. If this is set to True, the client listens on a port for a connection from the daemon and the server connects and uses that port to send any error messages. If this is false, the server sends error information through the main connection. The reason that StdError ports are used is that Rexec and RSH are primarily Unix-centered and Unix programs often use a StdError pipe and that data had to be treated separately from non-error related output.

The TIdRemoteCMDClient.ErrorReply and TIdRemoteCMDClient.ErrorMessage properties are not effected by this property at all.

If the user is behind a firewall, the TIdRemoteCMDClient.UseStdError property should be set to false because a connection to a Rexec or RSH daemon may fail if it can not connect to a user's StdError port.

Constructor for the object instance.

constructor Create(AOwner: TComponent); override;

Owner of the object instance.

Create is the constructor for the object instance. Create calls the inherited Create method and uses AOwner as the owner of the component. Create assigns IDRemoteFixPort as the default value for the UseReservedPorts property. Create also assigns IDRemoteUseStdErr as the default value for the UseStdError property.

Frees the object instance.

destructor Destroy; override;

Destroy is the destructor for the object instance. Destroy calls the inherited Destroy method prior to exiting.

This is an abstract method that is overridden in descendant classes.

function Execute(ACommand: String): String; virtual;

The command to execute on the remote system.

String - Descendant classes return the results from the command that was executed or no value if an error occurred. In TIdRemoteCMDClient.Execute, this simply returns a blank string.

This is an abstract method that is overridden in descendant classes. TIdRexec and TIdRSH override this will a function that calls an internal protected method called InternalExec passing the two authentication parameters required by the respective protocols. We do the coding this way because RSH uses the user's local User ID and the user's User ID on the remote host as part of it's authentication while Rexec requires the user's User ID on the remote machine and the password for authentication.