zhegvx(3) on Linux
The text 7dcdeadf3c0f, as Debian 3.1 (Sarge) shipped it.
compute selected eigenvalues, and optionally, eigenvectors of a complex generalized Hermitian-definite eigenproblem, of the form A*x=(lambda)*B*x, A*Bx=(lambda)*x, or B*A*x=(lambda)*x