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>    tcpserver offers a concurrency limit to protect you from running out
>    of processes and memory. When you are handling 40 (by default)
>    simultaneous connections, tcpserver smoothly defers acceptance of new
>    connections.
>    tcpserver also provides TCP access control features, similar to
>    tcp-wrappers/tcpd's hosts.allow but much faster. Its access control
>    rules are compiled into a hashed format with cdb, so it can easily
>    deal with thousands of different hosts.

>    This package includes a recordio tool that monitors all the input and
>    output of a server.

>    tcpclient makes a TCP connection and runs a program of your choice. It
>    sets up the same environment variables as tcpserver.

>    This package includes several sample clients built on top of
>    tcpclient: who@, date@, finger@, http@, tcpcat, and mconnect.

>    tcpserver and tcpclient conform to UCSPI, the UNIX Client-Server
>    Program Interface, using the TCP protocol. UCSPI tools are available
>    for several different networks.