efivar
Tools and libraries to manipulate EFI variables
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; version 2.1 of the License.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with this library. If not, see http://www.gnu.org/licenses/.
There is an ABI tracker for this project at ABI Laboratory.
WARNING
You should probably not run "make a brick" ever, unless you're already reasonably sure it won't permanently corrupt your firmware. This is not a joke.