The ucspi-tcp distribution contains tcpserver and tcpclient, which are easy-to-use command-line tools for building TCP client-server applications. tcpserver waits for incoming connections and, for each connection, runs a program of your choice. tcpclient makes a TCP connection and runs a program of your choice. 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.
ui is a user information utility that can display user information, list users from a given UID (or UID 500 by default), add a user to a group, rename a user along with his home directory and update his home directory files to reflect that change, list expired or locked users, change the shell for a user, and list users in an existing group.
user_info is a class to retrieve information about the browser the user is using to access the current site script. It can analyze the user agent string sent by the browser in the current HTTP request and extracts the type of browser, user machine operating system, user machine IP address, accepted character set encoding, language name, and whether the user is a spider/bot.