12.6.2
Using Substitutions in udev Rules
udev rules support the use of placeholders and substitutions. Use them in a similar
fashion as you would do in any other scripts. The following substitutions can be used
with udev rules:
%r, $root
The device directory, /dev by default.
%p, $devpath
The value of DEVPATH.
%k, $kernel
The value of KERNEL or the internal device name.
%n, $number
The device number.
%N, $tempnode
The temporary name of the device le.
%M, $major
The major number of the device.
%m, $minor
The minor number of the device.
%s{attribute}, $attr{attribute}
The value of a sysfs attribute (specied by attribute).
%E{variable}, $attr{variable}
The value of an environment variable (specied by variable).
%c, $result
The output of PROGRAM.
%%
The % character.
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