zpbcon(3) on Linux
The text 508871111d6c, as Debian 4.0 (Etch), Debian 3.1 (Sarge) shipped it.
estimate the reciprocal of the condition number (in the 1-norm) of a complex Hermitian positive definite band matrix using the Cholesky factorization A = U**H*U or A = L*L**H computed by ZPBTRF