[TUHS] What sparked lint? [Was: Unix stories]

Ron Natalie ron at ronnatalie.com
Fri Jan 6 03:46:38 AEST 2017

I remember being at an early UUG meeting and the group who did the UNIX port to the IBM series lamenting that it printed NUXI on boot because of byte order issues.    Don’t know if it was true, but NUXI became a synonym for UNIX byte order issues from then on.



The 8/32 indeed has some 370-ish stuff starting from the fact that it numbers the bits from the MSB end.   Amusingly, it has more minicomputerish other features.

One bizarre source of fun is that where as accessing a 16 bit quantity on an odd address on the PDP-11 gives you a bus error trap, the Interdata just ignores the low order bit and returns you the 16 bit value that you are pointing into the middle of.   Same things happen on 32-bit access (lower 2 bits ignored).    

For nostalgia, here’s a scan of an old 8/32 programmers manual:  http://bitsavers.trailing-edge.com/pdf/interdata/32bit/8-32/29-428_8-32_User_May78.pdf


Byte ordering got worked out when networking came in.     I worked on IBM’s AIX which was a productization of the UCLA LOCUS kernel.   The thing was a relatively tightly coupled multiprocessor system that allowed seamless execution of different binary types.    The machines we were working with were the 370 mainframe, the i386 (in the form of IBM PS/2’s), and a four processor i860 add in card IBM built called the W4.    The mainframe having the opposite byte ordering of the others.



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