Wicked Cool Shell Scripts

#51 Displaying Which Services Are Enabled

The first generation of Unix systems had a variety of system daemons, each of which listened to a specific port and responded to queries for a specific protocol. If you had a half-dozen services, you'd have a half-dozen daemons running. As Unix capabilities expanded, however, this wasn't a sustainable model, and an überdaemon called inetd was developed. The inetd service can listen to a wide range of different channels simultaneously, launching the appropriate daemon to handle each request as needed. Instead of having dozens of daemons running, it has only one, which spawns service-specific daemons as needed. In more recent years, a new, more sophisticated successor of inetd has become popular, called ...