Solution To Control-Z And Control-D Problems - Xerox DocuPrint Network Printer Series Guide Manual

Solution to control-Z and control-D problems

XEROX DOCUPRINT NPS GUIDE TO USING PAGE DESCRIPTION LANGUAGES
The recommended solution for the problems induced by control-D
and control-Z is to include the following PostScript definitions. They
can be loaded permanently, or prepended to jobs that have these
problems. These definitions catch illegal uses of these control
characters and also allow the legal uses (binary data) to pass
through untouched.
(\004) cvn {} def
character
(\032) cvn {} def
character
(\004\004) cvn {} def
(\004\032) cvn {} def
(\032\004) cvn {} def
(\032\032) cvn {} def
(\004\004\004) cvn {} def
(\004\004\032) cvn {} def
(\004\032\004) cvn {} def
(\004\032\032) cvn {} def
(\032\004\004) cvn {} def
(\004\032\004) cvn {} def
(\032\032\004) cvn {} def
(\032\032\032) cvn {} def
pattern
%
% The following code redefines PS operators and
names containing control
% characters.
commands will run without
% the undefined error.
be added here as needed.
%
(\004initgraphics) cvn {initgraphics} def
%remove ^D
(initgraphics\004) cvn {initgraphics}
def %remove ^D
(showpage\004) cvn {showpage}
def
% Examples of case sensitivity.
(sp\004) cvn {sp}
def
(Sp\004) cvn {Sp}
def
(SP\004) cvn {SP}
def
The preceding definitions use the following rules:
•
Isolated illegal characters. If the illegal characters occur alone
or only with some combination of other illegal characters, then
the resulting token may be redefined as an empty PostScript
procedure, as shown in this example:
(\004) cvn {} def
Note: It is not desirable to redefine the token as null because
this would leave a null object on the operand stack.
%ignore single ^D
%ignore single ^Z
%ignore ^D^D pattern
%ignore ^D^Z pattern
%ignore ^Z^D pattern
%ignore ^Z^Z pattern
%ignore ^D^D^D pattern
%ignore ^D^D^Z pattern
%ignore ^D^Z^D pattern
%ignore ^D^Z^Z pattern
%ignore ^Z^D^D pattern
%ignore ^D^Z^D pattern
%ignore ^Z^Z^D pattern
%ignore ^Z^Z^Z
Jobs containing the redefined
Additional lines may
%remove ^D
%remove ^D
%remove ^D
%remove ^D
POSTSCRIPT
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