Re: Adds redirect-lilypond-output option to lilypond-book (issue4664060)

[percival . music . ca]

LGTM, and fantastic website with testing info.


I have three requests for future work, but this patch should get pushed
first.

- the final "Child returned 1" doesn't tell me (as a user/doc-writer,
rather than phd student) anything.  How hard would it be to put the
"Look in logfile..." line after that one?
(a very quick skim suggests that this would be icky, so maybe forget
about it)
Or maybe just make the "child returned" into "Error: could not complete
command", or maybe "Error: child returned
__insert_error_code_interpretation__" ?

- it's a bit weird to see tons of output even when using the
--redirect-lilypond-output.  Would it be possible to make a
  --use-logfiles
option which automatically turns on --redirect-lilypond-output, but also
captures stderr+stdlog and writes *those* to a file?
(and maybe in addition to writing the log file, it would display the
"Error: child returned __blah_blah__" line)

- it would be great to automatically show the last X lines of the
logfile.  (but that's definitely something to do later on)


http://codereview.appspot.com/4664060/