Re: Piping contents of SVG directly to stdout

[Jean Abou Samra]

Le 15/07/2022 à 21:15, DoubleFelix a écrit :
> Hello,
>
> I'm using lilypond to programmatically generate sheet music. I already 
> have a system in place to crop the SVGs, but now I need to load them 
> in my software. I could use the default behavior of letting lilypond 
> write to some file, and then reading it, but file I/O tends to be 
> pretty expensive, especially when you're doing it in bulk like I am, 
> so I'd like to avoid that.
>
> My question is this: Is there a way to get lilypond to write the 
> output to stdout to save on performance, or do I need to use a file as 
> a middleman? For reference, my current command is:
> "lilypond --svg --loglevel=none file.ly <http://file.ly>"


I don't think this exists. On the other hand, I strongly
doubt that file I/O can prove expensive compared to the
time required to process the LilyPond file. For example,
with Python,

$ time lily -s --svg input/regression/parenthesize.ly

real    0m0,719s
user    0m0,637s
sys    0m0,061s

$ python
Python 3.10.5 (main, Jun  9 2022, 00:00:00) [GCC 12.1.1 20220507 (Red 
Hat 12.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from pathlib import Path
>>> from timeit import timeit
>>> timeit("Path('parenthesize.svg').read_bytes()", number=1000, 
globals=globals())
0.015240808002999984


As you can see, the time taken to read the output SVG
file was 2% of the time to compile the file in this example.

Best,
Jean