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C00002 00002	entry begin comment The (dummy) extension module of TEX.
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entry; begin comment The (dummy) extension module of TEX.

In order to extend TEX without changing other modules, you can supply
procedures for the null procedures declared here. Most of these procedures
are called when TEX's routines come up with a case that is ordinarily
undefined (usually when processing a node of type "whatsit");

require "TEXHDR.SAI" source_file;

internal procedure initext # do this when initializing TEX;
;
internal procedure extop # do this when "\x" sensed in user input;
;
internal procedure dumpext(integer p) # do this in procedure dumpnodelist;
;
internal procedure destroyext(integer p) # do this in procedure dsnodelist;
;
internal procedure eqdestroyext(integer p) # do this in procedure eqdestroy;
;
internal procedure hpackext(integer p) # do this in procedure hpackage;
;
internal procedure vpackext(integer p) # do this in procedure vpackage;
;
internal procedure pageext(integer p) # do this in the addtopage routine;
;
internal procedure justext(integer p) # do this in the justification routine;
;
internal procedure houtext(integer p; reference real x,y) # do this in shipout;
;
internal procedure voutext(integer p; reference real x,y) # do this in shipout;
;
comment in houtext, x and y are coordinates of the reference point, while
in voutext they are coordinates of the upper left corner;
internal procedure finishext # do this just before terminating TEX;
;
end