[tex-eplain] accents problem in pdf generated by eplain

[Laurence Finston]

Sorry, what I wrote was wrong.  This is the contents of dtemp.tex:

\input eplain

%% CM Roman 10

th{\'e}orie

%% EC Roman 1000

\font\rm=ecrm1000
\rm
th{\char233}orie

\bye


> Gesendet: Freitag, 21. Januar 2022 um 04:14 Uhr
> Von: "Laurence Finston" <Laurence.Finston at gmx.de>
> An: "Karl Berry" <karl at freefriends.org>
> Cc: tex-eplain at tug.org
> Betreff: Aw: Re: [tex-eplain] accents problem in pdf generated by eplain
>
> This is the contents of dtemp.tex:
> 
> \input eplain
> 
> \font\rm=ecrm1000
> \rm
> th{\char233}orie
> 
> \bye
> 
> These are the commands run:
> 
> tex dtemp && dvips -o dtemp.ps dtemp.dvi && ps2pdf dtemp.ps
> 
> The results are in the attached screenshots.  In evince, both {\'e} and é are searchable with é.  However, strangely, the orange box only covers half of the é resulting from {\'e}.  In Firefox, only é is searchable.
> 
> Since it obviously works, I haven't tested with pdftex, luatex, xetex ...
> 
> 
> > Gesendet: Freitag, 21. Januar 2022 um 00:46 Uhr
> > Von: "Karl Berry" <karl at freefriends.org>
> > An: gerald.ten at free.fr
> > Cc: tex-eplain at tug.org
> > Betreff: Re: [tex-eplain] accents problem in pdf generated by eplain
> >
> > Hi G\'erald - there are no special facilities in Eplain to make
> > PDF searching work, unfortunately. So this becomes a question about
> > getting searchable accents in PDF produced by plain TeX.
> > 
> > For pdfTeX, it is the primitives \pdfgentounicode and \pdfglyphtounicode
> > that ultimately define how the searching works. Whether those can be
> > coerced into working with the default CM 7-bit fonts, as Laurence
> > described, I don't know, but it may be possible.  Unfortunately I have
> > no recipe, either for that or for using 8-bit fonts like EC.
> > 
> > I didn't try it, but I suspect that using xetex or luatex, and 
> > OTF/TTF fonts (like Latin Modern), and Unicode characters for input
> > instead of TeX control sequences like \'e, would work.
> > 
> > However, to make TeX control sequences yield searchable characters in
> > plain TeX (with any engine), I don't know. I'm down to suggesting
> > posting the question on a more general forum, like the texhax at tug.org
> > mailing list or the tex.stackexchange.com forum, etc. Sorry. If you do,
> > and there are any positive answers, please let me know.
> > 
> > I'll try to at least mention this topic in the Eplain manual.
> > --all the best, karl.
> > 
> >