Telnet Component
Properties Methods Events Configuration Settings Errors
The Telnet Component is used to communicate with servers implementing the TELNET protocol.
Syntax
TipwTelnet
Remarks
The Telnet Component provides a simple interface to Telnet communications as specified by RFC 854. It allows sending of Telnet command codes to remote Telnet servers and it scans the input data for Telnet commands. Appropriate events are fired for received commands.
The connection interface is very similar to that of IPPort. The same properties and events are used for sending and receiving normal data, and the same property set is used for setting properties of the connection. The Telnet Component adds a number of properties like Command, DoOption, etc. which allow sending of Telnet commands to the other end. The respective events (Command, Do, etc.) are fired when the corresponding Telnet commands are received.
Property List
The following is the full list of the properties of the component with short descriptions. Click on the links for further details.
| AcceptData | Enables or disables data reception (the DataIn event). |
| BytesSent | The number of bytes actually sent after an assignment to DataToSend . |
| Command | A single character Telnet command code to be sent to the server. |
| Connected | Triggers a connection or disconnection. |
| DataToSend | A string of data to be sent to the remote host. |
| DontOption | A single character Telnet option code to be sent to the server with the Telnet DONT command. |
| DoOption | A single character Telnet option code to be sent to the server with the Telnet DO command. |
| DoSubOption | A Telnet SubOption to send to the server with the SubOption command. |
| FirewallAutoDetect | This property tells the component whether or not to automatically detect and use firewall system settings, if available. |
| FirewallType | This property determines the type of firewall to connect through. |
| FirewallHost | This property contains the name or IP address of firewall (optional). |
| FirewallPassword | This property contains a password if authentication is to be used when connecting through the firewall. |
| FirewallPort | This property contains the TCP port for the firewall Host . |
| FirewallUser | This property contains a user name if authentication is to be used connecting through a firewall. |
| KeepAlive | When True, KEEPALIVE packets are enabled (for long connections). |
| Linger | When set to True, connections are terminated gracefully. |
| LocalHost | The name of the local host or user-assigned IP interface through which connections are initiated or accepted. |
| LocalPort | The TCP port in the local host where IPPort binds. |
| RemoteHost | The address of the remote host. Domain names are resolved to IP addresses. |
| RemotePort | The Telnet port in the remote host (default is 23). |
| Timeout | A timeout for the component. |
| Transparent | When True, Telnet command processing is disabled. |
| UrgentData | A string of data to be sent urgently (out-of-band) to the remote host. |
| WillOption | A single character Telnet option code to be sent to the server with the Telnet WILL command. |
| WontOption | A single character Telnet option code to be sent to the server with the Telnet WONT command. |
Method List
The following is the full list of the methods of the component with short descriptions. Click on the links for further details.
| Config | Sets or retrieves a configuration setting . |
| Connect | Connect to a remote host. |
| Disconnect | Disconnect from the remote host. |
| DoEvents | Processes events from the internal message queue. |
| Send | Send data to the remote host. |
Event List
The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.
| Command | Fired when a Telnet command comes from the Telnet server. |
| Connected | Fired immediately after a connection completes (or fails). |
| ConnectionStatus | Fired to indicate changes in connection state. |
| DataIn | Fired when data is received from the remote host. |
| Disconnected | Fired when a connection is closed. |
| Do | Fired when a Telnet DO OPTION command comes from the Telnet server. |
| Dont | Fired when a Telnet DONT OPTION command comes from the Telnet server. |
| Error | Information about errors during data delivery. |
| ReadyToSend | Fired when the component is ready to send data. |
| SubOption | Fired when a Telnet SubOption command comes from the Telnet server. |
| Will | Fired when a Telnet WILL OPTION command comes from the Telnet server. |
| Wont | Fired when a Telnet WONT OPTION command comes from the Telnet server. |
Configuration Settings
The following is a list of configuration settings for the component with short descriptions. Click on the links for further details.
| ConnectionTimeout | Sets a separate timeout value for establishing a connection. |
| FirewallAutoDetect | Tells the component whether or not to automatically detect and use firewall system settings, if available. |
| FirewallHost | Name or IP address of firewall (optional). |
| FirewallPassword | Password to be used if authentication is to be used when connecting through the firewall. |
| FirewallPort | The TCP port for the FirewallHost;. |
| FirewallType | Determines the type of firewall to connect through. |
| FirewallUser | A user name if authentication is to be used connecting through a firewall. |
| KeepAliveTime | The inactivity time in milliseconds before a TCP keep-alive packet is sent. |
| KeepAliveInterval | The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received. |
| Linger | When set to True, connections are terminated gracefully. |
| LingerTime | Time in seconds to have the connection linger. |
| LocalHost | The name of the local host through which connections are initiated or accepted. |
| LocalPort | The TCP port in the local host where the component binds. |
| MaxLineLength | The maximum amount of data to accumulate when no EOL is found. |
| MaxTransferRate | The transfer rate limit in bytes per second. |
| RecordLength | The length of received data records. |
| TCPKeepAlive | Determines whether or not the keep alive socket option is enabled. |
| UseIPv6 | Whether to use IPv6. |
| TcpNoDelay | Whether or not to delay when sending packets. |
| AbsoluteTimeout | Determines whether timeouts are inactivity timeouts or absolute timeouts. |
| FirewallData | Used to send extra data to the firewall. |
| InBufferSize | The size in bytes of the incoming queue of the socket. |
| OutBufferSize | The size in bytes of the outgoing queue of the socket. |
| CodePage | The system code page used for Unicode to Multibyte translations. |