Tcp-related environment variables
The following environment variables describe a TCP connection. They are set up by tcp-env, tcpclient, and tcpserver. Note that TCPLOCALHOST, TCPREMOTEHOST, and TCPREMOTEINFO can contain arbitrary characters.
The string TCP.
The domain name of the local host, with uppercase letters converted to lowercase. If there is no currently available domain name for the local IP address, TCPLOCALHOST is not set.
The IP address of the local host, in dotted-decimal form.
The local TCP port number, in decimal.
The domain name of the remote host, with uppercase letters converted to lowercase. If there is no currently available domain name for the remote IP address, TCPREMOTEHOST is not set.
A connection-specific string, perhaps a username, supplied by the remote host via 931/1413/IDENT/TAP. If the remote host did not supply connection information, TCPREMOTEINFO is not set.
The IP address of the remote host.
The remote TCP port number.