[tlbuild] mtx and libp2c

[Bob Tennent]

 >|     >| > m-tx.lua suffice?
 >|
 >|I'm confused.
 >|Do users invoke "mtx" now or "prepmx" or "pmx" or some combination
 >|thereof?

Karl:  Currently, users can invoke the toolchain

prepmx -> pmx -> tex -> musixflx -> tex -> dvips -> ps2pdf

or just mtx, which is sym-linked to (or, on Windows, invokes) the
wrapper script mtx.lua that, by default, does all of the above
(and options to change the defaults).

 >|In any case, the idea is that they will invoke "m-tx.lua" now?
 >|
 >|That's surely fine as far as conflicts go, but in my experience it's
 >|suboptimal to embed the implementation language in the command name.
 >|With the -, I don't see a problem with just calling it "m-tx".

The script and the sym-link (or invoking binary) will, as proposed, be
m-tx.lua and m-tx, resp.

Best,
Bob