bin/texml returns 0 whether it succeeds or fails

[freddrueck]

Instead of providing a non-zero return value when something goes wrong, bin/texml always returns 0, so the obvious way of checking whether texml succeeded/failed in an external script that calls texml isn't possible.

[freddrueck]

Investigating texml more carefully, I see now that it actually operates on @argv, popping off filenames and trying to compile them to XML. I could imagine for some use cases it's useful to not have the perl script crash and compile all the documents which it is capable of compiling, however, if you are trying to call it externally it's really annoying not have it just crash when given bad input. At the very least, it would be nice to have the usage subroutine properly document this behavior; for the way I would like to use texml, it would be more useful for me to have texml only be capable of processing a single tex file at a time, but properly returning a non-zero value if it fails to compile that tex file.

I can probably implent a very dumb version of this by just adding a few lines of code to check if it created the output XML file and then issueing die; if didn't.

[freddrueck]

texml_die_if_xml_fails_to_compile_patch.txt

The attached patch implements a very primitive "die if XML didn't compile" for the first file that in @argv that fails to generate an XML output

[freddrueck]

I have now also submitted a pull request to merge changes that I think will resolve this issue, at least well enough for my intended use-case