Important unit specifiers

You can use the wildcard characters, called unit specifiers, in any unit configuration file. Unit specifiers substitute certain unit parameters and are interpreted at runtime.

Table 1. Important unit specifiers
Unit Specifier Meaning Description

%n

Full unit name

Stands for the full unit name including the type suffix. %N has the same meaning but also replaces the forbidden characters with ASCII codes.

%p

Prefix name

Stands for a unit name with type suffix removed. For instantiated units %p stands for the part of the unit name before the "@" character.

%i

Instance name

Is the part of the instantiated unit name between the "@" character and the type suffix. %I has the same meaning but also replaces the forbidden characters for ASCII codes.

%H

Hostname

Stands for the hostname of the running system at the point in time the unit configuration is loaded.

%t

Runtime directory

Represents the runtime directory, which is either /run for the root user, or the value of the XDG_RUNTIME_DIR variable for unprivileged users.

For a complete list of unit specifiers, see the systemd.unit(5) man page on your system.