osrelease

Os-release, typically found at /etc/os-release, is a standardized, machine-readable file that provides operating system identification data for Unix-like systems. It is defined by the freedesktop.org OS Release specification and is widely used by Linux distributions to expose consistent metadata about the installed OS. Some distributions also ship a vendor-specific copy at /usr/lib/os-release, which may be used as defaults or overridden by /etc/os-release.

The file is a plain text collection of KEY=VALUE pairs. Values may be quoted, especially when they contain spaces. The most common keys are NAME, VERSION, ID, ID_LIKE, VERSION_ID, and PRETTY_NAME. Additional optional keys can include HOME_URL, SUPPORT_URL, BUG_REPORT_URL, PRIVACY_POLICY_URL, CPE_NAME, and variant-related fields such as VARIANT and VARIANT_ID. The ID and ID_LIKE fields help describe the OS’s identity and its lineage (for example, Debian-like or Red Hat-like distributions).

Purpose and usage are central to os-release. It enables software to identify the operating system in a portable way without distro-specific parsing. Tools such as systemd and various package managers rely on these fields to tailor behavior or display appropriate information. In shells, a common pattern is to source the file to populate environment variables (for example, NAME, ID, VERSION_ID) or to parse a specific value with grep or awk.

Notes: while the spec aims for consistency, not all fields are present on every distribution, and implementations may vary. In container images, the file often reflects the base OS, which can differ from the host. See also the freedesktop.org OS Release Specification and related system tooling.