# How to know the number of pages in a PDF file?

I use graphicx to include pages of a PDF file. I want to know in LaTeX how many pages are in the file. How to do this?

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@Mathew wouldn't a simplistic solution be to insert a counter variable just before the includegraphics and after and get the difference? –  Yiannis Lazarides Jan 5 '11 at 13:19
@Yiannis, the topic starter is @fillieule. :-) –  xport Jan 5 '11 at 15:24
@xport Oops! yannis_was_sleeping! –  Yiannis Lazarides Jan 6 '11 at 4:00

pdfpages is obviously somehow able to get the number of pages of an included pdf. It does it with the pdftex primitive \pdflastximagepages. E.g.
\documentclass{article}