обзор иерархии файловой системы (File system hierarchy overview)
RUNTIME DATA
/run/
A "tmpfs" file system for system packages to place runtime
data in. This directory is flushed on boot, and generally
writable for privileged programs only. Always writable.
/run/log/
Runtime system logs. System components may place private logs
in this directory. Always writable, even when /var/log/ might
not be accessible yet.
/run/user/
Contains per-user runtime directories, each usually
individually mounted "tmpfs" instances. Always writable,
flushed at each reboot and when the user logs out. User code
should not reference this directory directly, but via the
$XDG_RUNTIME_DIR environment variable, as documented in the
XDG Base Directory Specification
[2].