initscripts uses files from the above directories to configure additional binary formats to register during boot in the kernel.
Each file contains a list of binfmt_misc kernel binary format rules. Consult binfmt_misc.txt[1] for more information on registration of additional binary formats and how to write rules.
Empty lines and lines beginning with ; and # are ignored. Note that this means you may not use ; and # as delimiter in binary format rules.
Each configuration file is named in the style of <program>.conf. Files in /etc/ overwrite files with the same name in /usr/lib/. Files in /run overwrite files with the same name in /etc/ and /usr/lib/. Packages should install their configuration files in /usr/lib/, files in /etc/ are reserved for the local administration, which possibly decides to overwrite the configurations installed from packages. All files are sorted by filename in alphabetical order, regardless in which of the directories they reside, to ensure that a specific configuration file takes precedence over another file with an alphabetically later name.
Example 1. /etc/binfmt.d/wine.conf example:
# Start WINE on Windows executables
:DOSWin:M::MZ::/usr/bin/wine:1. binfmt_misc.txt: http://www.kernel.org/doc/Documentation/binfmt_misc.txt