Finally, what does the "-o" option do?
-o,--output=FILE or FOLDER
Set the default output file to FILE or, if a folder with that name
exists,
direct the output to FOLDER, taking the file name from the input file.
The
appropriate suffix will be added (e.g. .pdf for pdf) in both cases.
For this command
$ lilypond mary.ly -o fred
my expectation is that the PDF output is placed in file fred.pdf rather
than
mary.pdf, but here is what occurs:
GNU LilyPond 2.16.0
Processing `mary.ly'
Parsing...
Interpreting music...[8]
Preprocessing graphical objects...
Finding the ideal number of pages...
Fitting music on 1 page...
Drawing systems...
Layout output to `mary.ps'...
Converting to `./mary.pdf'...
warning: cannot find file: `-o'
warning: cannot find file: `fred'
fatal error: failed files: "fred -o"