[TUHS] Program compiled on unix v6 works on unix v5

[Mark Longridge]

Ok, this is cheating a bit but I was wondering if I could possibly
compile my unix v6 version of unirubik which has working file IO and
run it under unix v5.

At first I couldn't figure out how to send a binary from unix v6 to
unix v5 but I did some experimenting and found:

tp m1r unirubik

which would output unirubik to mag tape #1 and

tp m1x unirubik

which would input unirubik from mag tape #1.

I don't know what cc does exactly but I thought "well if it compiles
to PDP-11 machine code and it's statically linked it could work". And
it actually does work!

I still want to try to get unirubik to compile under Unix v5 cc but
it's interesting that a program that uses iolib functions can work
under unix v5.

Mark