X11 header files - which package?

[Anthony Campbell <a.campbell@doctors.org.uk>]

Can someone kindly remind me which package is needed to supply X11
header files? I've come up against this one in the past but I can't
remember the solution.

Anthony



-- 
Anthony Campbell - running Gnu/Debian Linux (Windows-free zone)
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Human beings are perhaps never more frightening than when they are
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