/var/lib : Variable state information

This hierarchy holds state information pertaining to an application or the system. State information is data that programs modify while they run, and that pertains to one specific host. Users must never need to modify files in /var/lib to configure a package's operation.

State information is generally used to preserve the condition of an application (or a group of inter-related applications) between invocations and between different instances of the same application. State information should generally remain valid after a reboot, should not be logging output, and should not be spooled data.

An application (or a group of inter-related applications) must use a subdirectory of /var/lib for its data. There is one required subdirectory, /var/lib/misc, which is intended for state files that don't need a subdirectory; the other subdirectories should only be present if the application in question is included in the distribution.

/var/lib/<name> is the location that must be used for all distribution packaging support. Different distributions may use different names, of course.

The following directories, or symbolic links to directories, are required in /var/lib:

Directory Description
misc Miscellaneous state data

The following directories, or symbolic links to directories, must be in /var/lib, if the corresponding subsystem is installed:

Directory Description
<editor> Editor backup files and state (optional)
<pkgtool> Packaging support files (optional)
<package> State data for packages and subsystems (optional)
hwclock State directory for hwclock (optional)
xdm X display manager variable data (optional)

These directories contain saved files generated by any unexpected termination of an editor (e.g., elvis, jove, nvi).

Other editors may not require a directory for crash-recovery files, but may require a well-defined place to store other information while the editor is running. This information should be stored in a subdirectory under /var/lib (for example, GNU Emacs would place lock files in /var/lib/emacs/lock).

Future editors may require additional state information beyond crash-recovery files and lock files - this information should also be placed under /var/lib/<editor>.

Previous Linux releases, as well as all commercial vendors, use /var/preserve for vi or its clones. However, each editor uses its own format for these crash-recovery files, so a separate directory is needed for each editor.

Editor-specific lock files are usually quite different from the device or resource lock files that are stored in /var/lock and, hence, are stored under /var/lib.

This directory contains the file /var/lib/hwclock/adjtime.

In FHS 2.1, this file was /etc/adjtime, but as hwclock updates it, that was obviously incorrect.

This directory contains variable data not placed in a subdirectory in /var/lib. An attempt should be made to use relatively unique names in this directory to avoid namespace conflicts.