ulUnits (ULONG) - input

Page units.

Page units, as:

PU_ARBITRARY

Isotropic, arbitrary units defined by lHeight and lWidth. The page viewport is constructed to give equal X and Y spacing on the physical device, with at least one dimension of the page completely filling the corresponding default device dimension (that is, maximized window size and paper size). The origin is at the bottom left.
PU_PELS
Pel coordinates with the origin at the bottom left.
PU_LOMETRIC
Low resolution metric. These are units of 0.1 mm with the origin at the bottom left.
PU_HIMETRIC
High resolution metric. These are units of 0.01 mm with the origin at the bottom left.
PU_LOENGLISH
Units of 0.01 inch with the origin at the bottom left.
PU_HIENGLISH
Units of 0.001 inch with the origin at the bottom left.
PU_TWIPS
Twentieths of an imperial point. These are units of 1/1440 inch with the origin at the bottom left.
Other bits are reserved, and must be preserved and returned by GetPageUnits.