Hi, David Kastrup wrote:
Hi, sometimes on a long run one would like to be able to take a look at the current state of a PDF being produced.
I don't know whether there is something like a progressive PDF format: likely not.
I doubt it would be possible to do, that even with changes to pdftex. In any case you end up with either no embedded fonts at all, or a rather massive PDF with each page having its own font subsets and images.
But if I could send a signal to my PDFTeX/LuaTeX process, and this would cause it (at least if it would not currently be in a \shipout) to flush the current buffers, create a copy of the current PDF/DVI file under a snapshot name, properly finish/close it (writing reference table/DVI trailers) and then resume regular work, this would be quite dandy.
The idea is interesting, but I have absolutely no time to implement it. I fear that getting the details right may take quite some time (forking is easy, the tricky bit is duplicating the open files and file handles).
I often have the situation of starting a dead slow 1400 page compilation where I really need the full output, but can probably see after looking at a dozen pages whether or not the whole compilation will be rubbish, needs some minor change and restart.
Can't you just interrupt tex always and at the error prompt "I\end" ? If the PDF turns out to be OK after all, you will have to generate 1414 or so pages, a 10% overhead, not that bad compared to generating 2800. Best wishes, Taco