RPM - spec - Directory Standarization

FHS structure is making me crazy and I need to write down things since I forget how that FHS craziness works.

USR Directory
$XDG_DATA_DIRS (default: "/usr/local/share/:/usr/share/"): precedence-ordered set of system data directories. $XDG_CONFIG_DIRS (default: "/etc/xdg"): precedence-ordered set of system configuration directories.

HOME Directory
Your application should store and load data and configuration files to/from the directories pointed by the following environment variables:

$XDG_DATA_HOME (default: "$HOME/.local/share"): user-specific data files. $XDG_CONFIG_HOME (default: "$HOME/.config"): user-specific configuration files. $XDG_CACHE_HOME (default: "$HOME/.cache"): user-specific non-essential data files.

You should first determine if the file in question is:

A configuration file ($XDG_CONFIG_HOME:$XDG_CONFIG_DIRS); A data file ($XDG_DATA_HOME:$XDG_DATA_DIRS); or   A non-essential (cache) file ($XDG_CACHE_HOME).

Links

 * XDG Base Directory Specification