untrigraph(1) on Linux
The text 89d73e57b28f, as Debian 6.0 (Squeeze), Debian 5.0 (Lenny), Debian 4.0 (Etch), Debian 3.1 (Sarge), Debian 3.0 (Woody), Debian 2.2 (Potato), Debian 2.1 (Slink), Debian 2.0 (Hamm), Debian 1.3 (Bo), Debian 1.2 (Rex) shipped it.
remove trigraphs from C source code