% exectime.ps
% This file contains a page hook to calculate the execution time of a page
% Attention: PslibPageEndHook and PslibPageBeginHook are encapsulated 
% save and restore. 'save' leaves the current VM on the stack which is
% restored by 'restore' If your PslibPageBeginHook wants to leave additional
% data on the stack for PslibPageEndHook to pick up, you will have to exch
% it with the VM on the stack. The same is true for PslibPageEndHook. Since
% pslib calls 'save' and puts the page number on the stack, the data from
% PslibPageBeginHook is burried under these two elements.
%
% The PslibPageBeginHook command expects to find the following on the stack.
% page number
% ury (upper right corner of page, y coordinate)
% urx (upper right corner of page, x coordinate)
% lly (lower left corner of page, y coordinate)
% llx (lower left corner of page, x coordinate)
%
% PslibPageEndHook expects only the page number on the stack
%
% Use 'B' to define the command
/PslibPageBeginHook{
  pop pop pop pop pop realtime exch
} B
/PslibPageEndHook{
  pop exch
  /Helvetica findfont 8 scalefont setfont
	10 10 moveto (This page needed ) show
  realtime exch sub 10 (aaaaaaaa) cvrs show
	( ms for execution) show
} B