The software is licensed under GPLv2 or later. See COPYING for details.
C-M.E.S.S. is the C implementation of M.E.S.S., the successor to the LyaPack Toolbox for MATLAB. It is intended for the solution of symmetric linear and quadratic, differential and algebraic matrix equations with real, large, and sparse (or sparse + low-rank) coefficient matrices in the linear terms, low-rank quadratic and constant terms, and low-rank solutions. :The new version has been rewriten in large parts to fit the drastic upgrades in the Matlab releases since 2000.
See INSTALL.md for details.