On 2017-02-19 10:40, Lars Brinkhoff wrote:
Johnny Billquist wrote:
So one 36-bit word AAAAAAABBBBBBBCCCCCCCDDDDDDDEEEEEEEF becomes the five
octets 0AAAAAAA 0BBBBBBB CCCCCCC 0DDDDDDD FEEEEEEE.
I think you forgot one 0 before the Cs. :-)
Oh, yes.
But ok, such an encoding would work. But then your PDP-10 7-bit ASCII
files might not truly convert into 8-bit ASCII files... That final bit
can be a zero or a one... Some code on a PDP-10 did use that last bit
as well, when playing with 7-bit text, if I remember right.
That's right. I understand some programs encoded a line number in a
word with the final bit set. But I would not call those pure text
files.
I never heard of any other kind of text files with the final bit set.
But there could be.
I'm trying to remember if there were some who, for example, indicated
that this was the final word by setting the high bit. I'm sure someone
like Rich can chime in and tell if he know of any examples.
But I don't know how important you think the property of retaining
text file "compatibility" is.
If you were to display those converted files with line numbers, I guess
you would see five strange characters at the beginning of every text
line.
Yes.
I propse that handling this would be done outside of a 36-bit <-> octet
transformation. Same as line ending conversion between CRLF and
newline.
By "newline", I assume you mean LF. :-)
After all, there is actually no character named newline.
Although you might also be meaning whatever newline convention used on
whatever system you might be running on, in which case it might
sometimes be left as CR+LF, sometimes converted into just an CR or an
LF, and for some systems might be something completely different.
But if we're getting back into that you need a tool to convert the text
for local usability, then you loose that whole point about the suggested
format as transparently giving you the text again, and you might as well
go with another format that is a bit more compact?
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: [email protected] || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
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