XDGDATAHOME

XDG_DATA_HOME is an environment variable defined by the XDG Base Directory Specification that designates the base directory for user-specific data files. The canonical spelling is XDG_DATA_HOME; some references may use XDGDATAHOME as a shorthand, but the standard name uses underscores. If this variable is not set, applications should fall back to the default location: $HOME/.local/share. The directory is intended for per-user data files generated or stored by applications, such as user data, documents, and application state, rather than caches or configuration data.

In practice, XDG_DATA_HOME serves as the root for writable user data, and applications should create their own subdirectories within it as needed. It is distinct from the location used for configuration files (XDG_CONFIG_HOME) and caches (XDG_CACHE_HOME). For data that is installed system-wide and shared among users, applications typically consult XDG_DATA_DIRS, a colon-separated list of system-wide data directories (by default /usr/local/share:/usr/share). The combination of XDG_DATA_HOME and XDG_DATA_DIRS allows applications to separate per-user data from system-wide data and to locate resources in a predictable way across different environments.

Usage and compatibility notes: XDG_DATA_HOME is widely respected on Linux and other Unix-like systems implementing the XDG Base Directory Specification. Some legacy software may not honor these variables, in which case it may default to conventional paths like ~/.local/share or /usr/share. Developers are encouraged to rely on XDG_DATA_HOME for user data and to respect the existence of XDG_DATA_DIRS for system-wide resources.

See also: XDG Base Directory Specification, XDG_CONFIG_HOME, XDG_CACHE_HOME, XDG_RUNTIME_DIR.