[TUHS] DEC filenames

Johnny Billquist bqt at update.uu.se
Sun Mar 27 07:29:15 AEST 2016

On 2016-03-26 22:03, John Cowan wrote:
> Johnny Billquist scripsit:
>> SIXBIT dominated here for a long time. We see it both in the PDP-8,
>> but also the PDP-6 and its follow ons. RAD50 was the natural
>> extension of SIXBIT on a machine that did not have a word size that
>> was a multiple of 6.
> Well, for identifiers, yes.  But SIXBIT was quite general, especially
> if you repurposed two of the characters to mean "end of string" and
> "CR+LF".  The "@" was a popular choice for the former, perhaps because
> its encoding is 00; IIRC, "_" was popular for the latter.

Well, I was talking filenames (as also the subject says)... :-)

On the PDP-8, you sometimes saw @ used as a prefix character in SIXBIT. 
So you'd use @M to get a CR, and @J for an LF, and @@ would mark the end 
of the string. But not for filenames. But in code, since you sometimes 
used SIXBIT for string constants as well.


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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