-###############################################################################
-# Written by Chris Dunlap <cdunlap@llnl.gov>.
-# Modified by Brian Behlendorf <behlendorf1@llnl.gov>.
-###############################################################################
-# ZFS_AC_META: Read metadata from the META file. When building from a
-# git repository the ZFS_META_RELEASE field will be overwritten if there
-# is an annotated tag matching the form ZFS_META_NAME-ZFS_META_VERSION-*.
-# This allows for working builds to be uniquely identified using the git
-# commit hash.
-###############################################################################
-
+dnl #
+dnl # DESCRIPTION:
+dnl # Read meta data from the META file. When building from a git repository
+dnl # the ZFS_META_RELEASE field will be overwritten if there is an annotated
+dnl # tag matching the form ZFS_META_NAME-ZFS_META_VERSION-*. This allows
+dnl # for working builds to be uniquely identified using the git commit hash.
+dnl #
+dnl # The META file format is as follows:
+dnl # ^[ ]*KEY:[ \t]+VALUE$
+dnl #
+dnl # In other words:
+dnl # - KEY is separated from VALUE by a colon and one or more spaces/tabs.
+dnl # - KEY and VALUE are case sensitive.
+dnl # - Leading spaces are ignored.
+dnl # - First match wins for duplicate keys.
+dnl #
+dnl # A line can be commented out by preceding it with a '#' (or technically
+dnl # any non-space character since that will prevent the regex from
+dnl # matching).
+dnl #
+dnl # WARNING:
+dnl # Placing a colon followed by a space or tab (ie, ":[ \t]+") within the
+dnl # VALUE will prematurely terminate the string since that sequence is
+dnl # used as the awk field separator.
+dnl #
+dnl # KEYS:
+dnl # The following META keys are recognized:
+dnl # Name, Version, Release, Date, Author, LT_Current, LT_Revision, LT_Age
+dnl #
+dnl # Written by Chris Dunlap <cdunlap@llnl.gov>.
+dnl # Modified by Brian Behlendorf <behlendorf1@llnl.gov>.
+dnl #