Varrunexamplepid

Varrunexamplepid is a placeholder identifier used in documentation and example code to refer to the process identifier (PID) of a running daemon or service. It is not a standard system term, but rather a generic label that helps illustrate how a program should reference a PID file or the PID itself in real deployments.

In typical Unix-like environments, a daemon records its PID in a PID file to signal that it is active and to aid management scripts. The conventional location is under /var/run (often a symlink to /run on modern systems), with a filename like daemonname.pid. In examples, varrunexamplepid stands in for such a file or variable, showing where the actual daemon’s PID would be stored or accessed. The content of a PID file is usually a single numeric line containing the process ID.

Management workflows commonly involve starting a daemon only if no existing instance is running, achieved by reading the PID from the file and verifying that the process exists. On shutdown, the daemon removes the PID file. If a stale or orphaned PID file remains, scripts may check for the corresponding process and, if absent, clean up the file before starting a new instance.

Variations exist across init systems: traditional SysV-style scripts often manipulate /var/run, while modern systems use /run and may rely on native service managers. Security considerations include proper file permissions, atomic creation of the PID file, and preventing tampering.

In practice, varrunexamplepid serves as a teaching aid to explain how a daemon should advertise and manage its running state through a PID file. See also PID file, /var/run, /run, daemon, and process management utilities.