<div dir="ltr"><div dir="ltr"><div>I imagine that many systems at the time had comparable restrictions on<br>filenames (thus the original idea document for TEX [sic] being in a<br>file called TEXDR.AFT rather than say TEX.DRAFT).<br></div>There's a funny remark related to extensions at the start of one of<br><div>Knuth's TeX internals videos in 1982, suggesting that extensions were<br>already becoming an issue as three-letter names were being "taken".<br>The background (from the start of the video) is that he had just<br>announced the extension .log for the transcript (log) file written out<br>by TeX, and someone objected. You can watch the response yourself<br>(<a href="https://www.youtube.com/watch?v=PnGcMILNhRI&list=PLABJEFgj0PWWQCiXDJ6UmR8BWQ6YcyVHv&t=60">1:00 to 1:35 in Session 11</a>); sorry for wasting 35 seconds of your<br>time if you don't find it as funny as I do. :-)<br></div><div><a href="https://www.youtube.com/watch?v=PnGcMILNhRI&list=PLABJEFgj0PWWQCiXDJ6UmR8BWQ6YcyVHv&t=60">https://www.youtube.com/watch?v=PnGcMILNhRI&list=PLABJEFgj0PWWQCiXDJ6UmR8BWQ6YcyVHv&t=60</a><br></div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, 11 Dec 2020 at 09:31, Philip Taylor <<a href="mailto:P.Taylor@hellenic-institute.uk">P.Taylor@hellenic-institute.uk</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<div>barbara beeton wrote:<br>
</div>
<blockquote type="cite"><br>
A 3-letter file extension has nothing to do with DOS, which didn't
even
<br>
exist when TeX was being developed. It's a limit of the SAIL
operating
<br>
system for the DECSystem 10, on which TeX and MF were developed.
The
<br>
limit for file names was 6.3. Traces of this can still be seen in
the
<br>
names of the Computer Modern fonts, several of which would be more
<br>
easily understood with a few more letters in their names.<br>
</blockquote>
<br>
Well, Barbara is never wrong, by definition, but CP/M, which
pre-dates both MS/DOS and TeX, (CP/M having been born in 1974) also
used an 8.3 filen-aming convention :<br>
<br>
<blockquote type="cite">[<a href="https://en.wikipedia.org/wiki/CP/M" target="_blank">CP/M</a>] File names
were specified as a string of up to eight characters, followed by
a period, followed by a file name extension of up to three
characters (<a href="https://en.wikipedia.org/wiki/8.3_filename" target="_blank">"8.3"
filename format</a>). The extension usually identified the type
of the file. For example, <code>.COM</code> indicated an
executable program file, and <code>.TXT</code> indicated a file
containing <a href="https://en.wikipedia.org/wiki/ASCII" target="_blank">ASCII</a>
text.
</blockquote>
<br>
<i>Philip Taylor</i><br>
<br>
</div>
</blockquote></div></div>