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<div class="moz-cite-prefix">Enrico Gregorio wrote:<br>
<br>
</div>
<blockquote type="cite"
cite="mid:A3F2C047-D209-4D0B-890A-EB1BF5141143@gmail.com">
<pre wrap="">If one tries the following test file
\s^^?E
with any plain TeX engine (tex, pdftex, xetex, luatex),
pressing 1 after the “undefined control sequence”
error yields
! Undefined control sequence.
l.1 \s
^^?H
</pre>
</blockquote>
<br>
[snip]<br>
<br>
All fine here under Windows 7 Enterprise (64-bit) — the initial "E"
does not mutate into an "H", and all proceeds normally.<br>
<br>
<blockquote type="cite">C:\Users\Philip Taylor_2>tex \relax
\s^^?E<br>
This is TeX, Version 3.14159265 (TeX Live 2020/W32TeX) (preloaded
format=tex)<br>
! Undefined control sequence.<br>
<*> \relax \s<br>
^?E<br>
? 1<br>
<*> \relax \s^<br>
?E<br>
? q<br>
OK, entering \batchmode<br>
C:\Users\Philip Taylor_2></blockquote>
<br>
Philip Taylor<br>
<br>
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