\displayLilyMusic function

[James Lowe]

Hello,

While browsing around the NR I came across a 'what happens if a user 
uses windows' comment in one of the *.itely files.

Specifically regarding this section.


> 3.3.4 Displaying LilyPond notation
> Displaying a music expression in LilyPond notation can be done using the music 
> function
> \displayLilyMusic. For example,
> {
>   \displayLilyMusic \transpose c a, { c4 e g a bes }
> }
>    will display
> { a,4 cis e fis g }
>    By default, LilyPond will print these messages to the console along with all 
> the other mes-
> sages. To split up these messages and save the results of \display{STUFF}, 
> redirect the output
> to a file.
> lilypond file.ly >display.txt


Now this all seems to work however I always get a PDF file created even 
if the *.ly file contains

\version "2.13.6"

{
  \displayLilyMusic \transpose c a, { c4 e g a bes }
}

I just want to check that that is expected behaviour (i.e. without any 
CLI switches 'Lilypond myfile.ly' with just the above information should 
create a PDF.

Thanks for your time.

James