nelu wrote:
Some of the older PDP implementations had non-8-bit byte sizes.
Terminology: this sounds like you mean different C implementations on
one "PDP" machine, or several "PDP" machines that implement a common
architecture. In fact Programmed Data Processor was the name used for
a series of machines by DEC (Digital Equipment Corporation) that were
mostly quite different, some with multiple implementations. There were
four models of PDP-10 namely KA-10, KI-10, KL-10, KS-10 which
implemented the same architecture, which was nearly the same as PDP-6.
There were several models of PDP-8 of which I recall 8/s, 8/i, 8/e,
8/m and 8/a, which implemented one architecture, nearly the same as
PDP-5 and similar to PDP-12 aka LINC-12, but very different from -6
and -10. PDP-7 and -9 were similar, and I believe also similar to -4
and -1, but different from -6/10 and -5/8/12. There were many
(numbered) models of PDP-11 like 11/20, 11/40, 11/45, 11/34, 11/70
etc. all implementing basically the same architecture, different from
all other PDP series machines.
There were also quite a few non-DEC machines with non-8-bit bytes.
Like any other implementation, just with wider than usual bytes.
The same way that 8-bit byte machines communicate through 7-pin din
connectors.
Any number of ways. But none of them are necessarily topical in
comp.lang.c.
In the early days of the Internet and before that ARPANET, this was a
significant issue and there are a number of features (still) specified
especially in FTP to deal with data exchange with systems having a
byte other than 8 bits, no longer used today except perhaps
occasionally by mistake.
- David.Thompson1 at worldnet.att.net