[tex-live] requirements for addition in shell_escape_commands

[Élie Roux]

> I can't look in detail right now, sorry, but here's what comes to mind:
> if reading from a file, it should use kpse_in_name_ok[_silent] to ensure
> it's allowed to read from it, and if writing to a file,
> kpse_out_name_ok[_silent].  There are equivalent options in kpsewhich.
> I imagine you might not want to link with kpathsea; perhaps a wrapper
> script is the answer.

I see two options here:
 - a compilation option to link with kpse, that would be only used in
TeXLive build (it seems too complex to ask users downloading gregorio on
github to compile kpse library first)
- a wrapper script, gregorio-safe

A few questions:
- would the first solution be acceptable? This would mean that users
installing gregorio from github on top of the TeXLive installation would
have an "unsafe" gregorio in shell_escape_commands

- where can I find the documentation of kpse_in_name_ok?

- Norbert: under Debian, pkg-config --cflags --libs kpse doesn't find
kpse, what is the easiest way to make some tests? should I checkout a
part of svn repository, build kpse and link against it?

- if a script solution is taken, what would be the most appropriate
language? Perl seems a good option as it's shipped with TeXLive, but
would it be safe enough to be in the shell_escape_commands? One of the
constraints here is that it would be good if gregorio users building
from github would be able to build this script too, so C with kpse
bindings would have the same problem as the kpse binding with the main
executable... Or maybe the wrapper script could be only in TeXLive, and
users installing gregorio on top of TeXLive would still call
gregorio-safe, but it would itself call the new gregorio... What do you
think?

>  Or maybe a mode where it can only use
> stdin/stdout.  I'm not sure.

We tried stdin/stdout only, but it would require lua to plug on both
stdin and stdout, which is a bit complex...

> The source should not require gcc; other compilers are used.
> (I doubt this will be hard.)

Shouldn't be a problem... It compiles in a mingw32 environment, and we
made everything with clang compatibility in mind. What other compilers
should I try?

> Not a stopper, but the name "gregorio" makes me think of our friend
> Enrico, rather than anything about chant, let alone chant+tex ...

As Axel noted, it depends a lot on the context... Gregorio is almost 9
years old now, it seems difficult to rename it...

Thank you very much,
-- 
Elie