Saving the font subset on the memory instead of writing on disk

[keto33]

This is a follow-up to my previous issue. I just wonder if there is any plan for saving the subset font on the memory instead of writing it on the disk?

This feature should be very helpful for the purpose of embedding the font in PDF.

[bsweeney]

I think that's probably a worthwhile update. Something similar has been suggested for Dompdf.