clalsd(3) on Linux
The text 36b94a2dddf8, as Debian 4.0 (Etch), Debian 3.1 (Sarge) shipped it.
use the singular value decomposition of A to solve the least squares problem of finding X to minimize the Euclidean norm of each column of A*X-B, where A is N-by-N upper bidiagonal, and X and B are N-by-NRHS