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Suppress Telnet NUL at end-of-line for Telnet transmission. Windows systems only.


[Miscellaneous]    TelnetNUL=n

n is either 1 (true) or 0 (false). The default value is 0.


On output, a Telnet network virtual terminal (NVT) performs the following default end-of-line behavior: either issues a carriage return character (CR) followed by a linefeed character (LF), or issues a CR followed by NUL (if no LF is issued). TelnetNUL affects the issuance of the NUL character in the second case. When TelnetNul is enabled (n = 1), the Telnet virtual terminal suppresses the NUL character.

This setting applies only to Windows systems; it is ignored on UNIX®, and Linux configurations, in which Telnet is supplied by the operating system vendor.

Changing This Parameter

On the Compatibility page of the Management Portal (System Administration > Configuration > Additional Settings > Compatibility), in the TelnetNUL row, click Edit. Select TelnetNUL to enable this setting.

Instead of using the Management Portal, you can change TelnetNUL in the Config.Miscellanous class (as described in the class reference) or by editing the CPF in a text editor (as described in the Editing the Active CPF section of the “Introduction to the Configuration Parameter File” chapter in this book).

To change this parameter for a single process only (as opposed to instance-wide), use the TelnetNUL() method of the %SYSTEM.Process class. See the class reference for details.