pstrrfs(3) on Linux
The text d202d9dafceb, as Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie), Debian 7 (Wheezy), Debian 6.0 (Squeeze), Debian 5.0 (Lenny), Debian 4.0 (Etch), Debian 3.1 (Sarge), Debian 3.0 (Woody), Debian 2.2 (Potato) shipped it. The page shows this text now.
provide error bounds and backward error estimates for the solution to a system of linear equations with a triangular coefficient matrix