We wrote our own versions of more. Here is one from the roughly-PWB1 systems at MIT: http://ana-3.lcs.mit.edu/~jnc/tech/unix/s2/p.c but on looking at it, I'm not 100% sure it's the one I used there (which is documented in the MIT UPM). Here's one I wrote for myself for use on V6: http://mercury.lcs.mit.edu/~jnc/tech/V6Unix.html#UCmds before I retrieved all the MIT sources (above), if you want somthing to actually use on V6/V7. Noel