| File | Size | Date |
|---|---|---|
| etc | dir | |
| usr | dir |
Sixth Edition UNIX was released by Bell Laboratories in May 1975.
It was designed to run on the PDP-11s with 18-bit addressing such as the PDP-11/40, 11/45 and 11/70. The kernel's image size was around 29 Kbytes. This edition introduced the `Portable C Library' written by Mike Lesk, which would evolve into the Standard I/O library.
The files in this area were supplied by Dennis Ritchie.