+##
+## e_colwd = basic width of a column in pixels
+## e_hextra = extra horizontal width in pixels
+## Width of an N-column Emacs frame in pixels will be
+## N*e_colwd + e_hextra
+## e_colchars = width of a column in Emacs `-geometry' units
+## e_cextra = extra horizontal width in Emacs `-geometry' units
+## So an N-column frame should be reported to Emacs as being
+## N*e_colchars + e_cextra geometry units wide
+## e_lineht = height of a character line in pixels
+## e_vextra = number of additional vertical cruft pixels
+## So an N-line Emacs frame takes N*e_lineht + e_vextra pixels