cptsv(3) on Linux
The text 2c7e911bfa69, as Debian 4.0 (Etch), Debian 3.1 (Sarge) shipped it.
compute the solution to a complex system of linear equations A*X = B, where A is an N-by-N Hermitian positive definite tridiagonal matrix, and X and B are N-by-NRHS matrices