slasr(3) on Linux
The text fd855f534a52, as Debian 1.3 (Bo) shipped it.
perform the transformation A := P*A, when SIDE = 'L' or 'l' ( Left-hand side ) A := A*P', when SIDE = 'R' or 'r' ( Right-hand side ) where A is an m by n real matrix and P is an orthogonal matrix,