Re: Output PDF to stdout

[Volodymyr Prokopyuk]

Thank you very much for your thoughts!

I expected that the PDF output to stdout would be difficult to implement due to multiple Lilypond backends, and, probably, is not a real bottleneck in PDF generation. It is nice to know that intermediary files are already handled by a FS cache, and can be externally optimized by using a RAM disk.

Thank you,

Vlad

On Fri, Jan 5, 2024 at 4:46 AM David Wright <lilylis@lionunicorn.co.uk> wrote:

On Thu 04 Jan 2024 at 23:34:28 (+0100), Volodymyr Prokopyuk wrote:
>
> I know that lilypond can receive a source.ly file from the stdin by
> using lilypond
> -. Is it possible for lilypond to output PDF to the stdout?
>
> My motivation behind using lilypond in a pipeline is to speed up PDF
> generation by avoiding storing intermediary files on disk. The pipeline I'd
> like to implement is
> cat source.ly | lintLy | lilypond - | optimizePDF > score.pdf
> Currently lilypond engraves PDF on disk, so a PDF optimizer has to read,
> optimize, and substitute PDF on disk.

You could create a RAM disk to hold your intermediate files,
something along the lines of:

   Ramdir="/dev/shm/${FUNCNAME[0]}$(printf '%(%s)T' -1)"
 $ mkdir -p "$Ramdir"

The first line (which I run in a bash function, for a quite different
purpose) creates a pseudounique but recognizable name, and the second
line creates the directory.

Cheers,
David.