Linux Shell Scripting Cookbook - Third Edition

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These techniques will find services that have been started at root with the SysV or systemd initialization scripts. However, services may be started manually, or in a boot script, or with xinetd.

The xinetd daemon functions in a similar way to init: it starts services. Unlike init, the xinitd daemon only starts a service when it's requested. For services such as SSH, which are required infrequently and run for a long time once started, this reduces the system load. Services such as httpd that perform small actions (serve a web page) frequently are more efficient to start once and keep running.

The configuration file for xinet is /etc/xinetd.conf. The individual service files are commonly stored in /etc/xinetd.d.

The individual ...