pdfSetPSPaperSize
Set the PostScript paper size.
void pdfSetPSPaperSize(int width, int height)
This function sets the paper size for PostScript output. The paper
size is specified as a width and height, in PostScript points (one
point = 1/72 inch = 0.353 mm).
PDF pages which are larger than the specified paper type will be scaled down to fit.
This setting is global, i.e., it affects XpdfPS calls on all PDF handles.
C:
/* same as pdfSetPSPaperType("A4"); */
pdfSetPSPaperSize(595, 842);