zhegvx(3) on Linux
The text d7098f6fbcd9, as Debian 4.0 (Etch) 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