stable 1999.02.17

1 files changed, 1212 insertions, 958 deletions

diff --git a/tex/context/base/spec-ini.tex b/tex/context/base/spec-ini.tex
index b26f067f1..000f35841 100644
--- a/tex/context/base/spec-ini.tex
+++ b/tex/context/base/spec-ini.tex
@@ -1,958 +1,1212 @@
-%D \module

-%D   [       file=spec-ini,

-%D        version=1996.01.25,

-%D          title=\CONTEXT\ Special Macros,

-%D       subtitle=Initialization,

-%D         author=Hans Hagen,

-%D           date=\currentdate,

-%D      copyright={PRAGMA / Hans Hagen \& Ton Otten}]

-%C

-%C This module is part of the \CONTEXT\ macro||package and is

-%C therefore copyrighted by \PRAGMA. Non||commercial use is 

-%C granted. 

-

-%D Specials are \TEX's channel to the outside world. They make

-%D \TEX\ even more platform independant and permit easy

-%D adaption to new developments. One major drawback of specials

-%D is that they have to be supported by printer drivers. We've

-%D tried to overcome this problem by implementinmg specials as

-%D a sort of drivers themselves.

-

-\writestatus{loading}{Context Special Macros / Initialization}

-

-\unprotect

-

-\startmessages  dutch  library: specials

-  title: specials

-      1: -- geladen

-      2: verdere nesting is niet toegestaan --

-      3: -- gereset

-      4: commando -- bestaat niet

-      5: definitiefile -- wordt geladen

-      6: nesting is niet toegestaan

-\stopmessages

-

-\startmessages  english  library: specials

-  title: specials

-      1: -- loaded

-      2: no deeper nesting is permitted --

-      3: -- is reset

-      4: command -- does not exist

-      5: loading definition file --

-      6: nesting is not permitted

-\stopmessages

-

-\startmessages  german  library: specials

-  title: spezielles

-      1: -- geladen

-      2: Keine tiefere Verschachtelung erlaubt --

-      3: -- ist zurueckgesetzt

-      4: Befehl -- existiert nicht

-      5: Lade Definitionsdatei --

-      6: Verschachtelung nicht erlaubt

-\stopmessages

-

-\startmessages  dutch  library: interactions

-     21: -- code tussengevoegd

-\stopmessages

-

-\startmessages  english  library: interactions

-     21: -- code inserted

-\stopmessages

-

-\startmessages  german  library: interactions

-     21: -- Code eingefuegt

-\stopmessages

-

-%D Because there is no standardization in the use of specials,

-%D more than one driver or program can be supported. The

-%D specials are grouped in libraries. Some of these are

-%D general, such as the \type{postscript} library, some are

-%D tuned to a special kind of program, like the \type{pdf}

-%D ones, and some support a specific driver, as we can see in

-%D the \type{yandy} library. A library is build with the

-%D commands:

-%D

-%D \starttypen

-%D \startspecials[name][inheritance]

-%D

-%D \definespecial\none{...}

-%D \definespecial\onlyone#1{...}

-%D \definespecial\alot#1#2#3#4{...}

-%D

-%D \stopspecials

-%D \stoptypen

-%D

-%D Because drivers show some overlap in their support of

-%D specials, a mechanism of inheritance is implemented. The

-%D predefined libraries show this feature.

-%D

-%D Every special has to be predefined first. We  do this with

-%D the command:

-%D

-%D \starttypen

-%D \installspecial [\none]    [and] [0]

-%D \installspecial [\onlyone] [and] [1]

-%D \installspecial [\alot]    [or]  [4]

-%D \stoptypen

-%D

-%D This means as much as: there is a special names

-%D \type{\none} which has no arguments and has more than one

-%D appearance. The special \type{\alot} on the other hand has

-%D four arguments and is only defined once. Every instance in

-%D the libraries of a special of category \type{and} is

-%D executed when called upon, but only one special of

-%D category \type{or} can be active. Most of the

-%D \type{postscript}||specials are of category \type{or},

-%D because they tend to interfere with driver specific ones.

-%D The interactive specials of \type{dviwindo} and \type{pdf}

-%D are an example of specials that can be called both.

-%D

-%D A library is defined in a file with the name

-%D \type{spec-...}. We load a library with the command:

-%D

-%D \starttypen

-%D \usespecials [list]

-%D \stoptypen

-%D

-%D where the list can contain one or more file tags, the

-%D \type{...} in the filename. The keyword \type{reset}

-%D resets all loaded specials. This is equivalent to

-%D \type{\resetspecials}.

-

-%D Although a mechanism of nesting can be implemented, we

-%D prefer to use a inheritance mechanism as mentioned. Calls

-%D upon \type{\usespecials} within a \type{\startspecials}

-%D would lead to confusion and errors.

-

-\newif\ifinheritspecials

-

-%D We define some local constants and variables. They look a

-%D bit horrible but we don't want conflicts.

-

-\def\@@specfil@@{@@specfil@@}

-\def\@@speclst@@{@@speclst@@}

-\def\@@speccat@@{@@speccat@@}

-\def\@@specarg@@{@@specarg@@}

-\def\@@specexc@@{@@specexc@@}

-

-\def\currentspecial      {}

-\def\currentspecialfile  {}

-\def\preloadedspecials   {}

-

-%D \macros

-%D   {preloadspecials}

-%D   {}

-%D

-%D The following command can be used to show the loaded list

-%D of specials.

-

-\def\preloadspecials%

-  {\doifsomething{\preloadedspecials}

-     {\showmessage{\m!specials}{1}{\preloadedspecials}}}

-

-%D \macros

-%D   {startspecials}

-%D   {}

-%D

-%D Every library has a unique name, which is given as the first

-%D argument to \type{\startspecials}. When another library is

-%D defined with the same name, previous specials can be

-%D overruled. The name may differ from the file||tag.

-%D

-%D The optional second argument can consist of a list of

-%D libraries that are to be loaded first. This list can contain

-%D file||tags or names of libraries. Names are often more

-%D meaningful.

-

-\def\dostartspecials[#1][#2]%

-  {\let\mainspecialfile=\currentspecialfile

-   \doifelsenothing{#2}

-     {\inheritspecialsfalse}

-     {\ifinheritspecials

-        \showmessage{\m!specials}{2}{(#2)}%

-      \else

-        \inheritspecialstrue

-        \processcommalist[#2]\dousespecials

-        \inheritspecialsfalse

-      \fi}%

-   \doifelsenothing{#1}

-     {\def\currentspecial{\s!unknown}}

-     {\def\currentspecial{#1}}%

-   \let\currentspecialfile=\mainspecialfile

-   \setevalue{\@@specfil@@\currentspecial}{\currentspecialfile}%

-   \unprotect

-   \addtocommalist{\currentspecial}\preloadedspecials}

-

-\def\startspecials%

-  {\dodoubleempty\dostartspecials}

-

-\def\stopspecials%

-  {\def\currentspecial{}%

-   \protect}

-

-%D \macros

-%D   {installspecial,

-%D    resetspecials}

-%D   {}

-%D

-%D We have to install specials before we can define and use

-%D them. The command itself is defined as a call to another

-%D command that executes one or more user||defined specials,

-%D depending of it's category: \type{or} versus \type{and}.

-%D

-%D The command \type{\installspecial} takes three

-%D (non||optional) arguments: the name of the command, the

-%D category it belongs to and the number of arguments it

-%D takes.

-%D

-%D With \type{\resetspecials} we can unload the predefined

-%D specials.

-

-\def\@@allspecials{}

-

-\def\doinstallspecial[#1][#2][#3]%

-  {\setvalue{\@@speclst@@\string#1}{}%

-   \setvalue{\@@speccat@@\string#1}{#2}%

-   \setvalue{\@@specarg@@\string#1}{#3}%

-   \addtocommalist{\string#1}\@@allspecials

-   \def#1{\executespecial#1}}

-

-\def\installspecial%

-  {\dotripleargument\doinstallspecial}

-

-\def\resetspecials%

-  {\def\docommando##1%

-     {\setvalue{\@@speclst@@##1}{}}%

-   \processcommacommand[\@@allspecials]\docommando

-   \showmessage{\m!specials}{3}{\preloadedspecials}%

-   \def\preloadedspecials{}%

-   \def\@@allspecials{}}

-

-%D \macros

-%D   {definespecial}

-%D   {}

-%D

-%D The command \type{\definespecial} take the place of

-%D \type{\def} in the definition of a special. Just to be

-%D sure, we first check if the command is permitted, i.e.

-%D installed. If not, we give a warning and gobble the

-%D illegal command in an quite elegant way.

-%D

-%D If the command can be combined (\type{and}) with others,

-%D we append it to a list, otherwise (\type{or}) it becomes

-%D the only item in the list.

-

-\def\definespecial#1%

-  {\ifx#1\undefined

-     \showmessage{\m!specials}{4}{\string#1}%

-     \def\next%

-       {\def\@@illegalspecial@@}%

-   \else

-     \def\next%

-       {\doifelse{\getvalue{\@@speccat@@\string#1}}{or}

-          {\edef\@@newspeclst@@{\currentspecial}}

-          {\edef\@@newspeclst@@{\getvalue{\@@speclst@@\string#1}}%

-           \addtocommalist{\currentspecial}\@@newspeclst@@}%

-        \setevalue{\@@speclst@@\string#1}{\@@newspeclst@@}%

-        \setvalue{\currentspecial\string#1}}%

-   \fi

-   \next}

-

-%D \macros

-%D   {usespecials}

-%D   {}

-%D

-%D We use \type{\usespecials} to load a specific library.

-%D This command is only permitted outside de definition part.

-

-\def\dousespecials#1%

-  {\doifelse{#1}{\v!reset}

-     {\resetspecials}

-     {\doifdefinedelse{\@@specfil@@#1}

-        {\edef\currentspecialfile{\getvalue{\@@specfil@@#1}}}

-        {\edef\currentspecialfile{#1}}%

-      \makeshortfilename[\f!specialprefix\currentspecialfile]%

-      \showmessage{\m!specials}{5}{\currentspecialfile}%

-      \startreadingfile

-      \readsysfile{\shortfilename}{}{}%

-      \stopreadingfile

-      \showmessage{\m!specials}{1}{\preloadedspecials}}}

-

-\def\usespecials[#1]%

-  {\doifelsenothing{\currentspecial}

-     {\processcommalist[#1]\dousespecials}

-     {\showmessage{\m!specials}{6}{}}}

-

-%D \macros

-%D   {executespecials}

-%D   {}

-%D

-%D The command \type{\executespecials} is used to execute the

-%D defined specials. Once a special is installed, the special

-%D itself calls for this command, so it's not needed outside

-%D this module. One can use it if wanted.

-%D 

-%D A former implementation grouped the execution. Recent 

-%D additions however |<|like the specials that implement object 

-%D handling|>| asked for non||grouped execution. 

-

-\def\executespecials#1#2%

-  {\def\doonespecial##1%

-     {\getvalue{##1\string#1}#2\relax}%

-   \processcommacommand

-     [\getvalue{\@@speclst@@\string#1}]\doonespecial}

-

-\def\executespecial#1%

-  {\expandafter\ifcase\getvalue{\@@specarg@@\string#1}\relax

-     \def\next%

-       {\executespecials#1{}}%

-   \or

-     \def\next##1%

-       {\executespecials#1{{##1}}}%

-   \or

-     \def\next##1##2%

-       {\executespecials#1{{##1}{##2}}}%

-   \or

-     \def\next##1##2##3%

-       {\executespecials#1{{##1}{##2}{##3}}}%

-   \or

-     \def\next##1##2##3##4%

-       {\executespecials#1{{##1}{##2}{##3}{##4}}}%

-   \or

-     \def\next##1##2##3##4##5%

-       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}}}%

-   \or

-     \def\next##1##2##3##4##5##6%

-       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}}}%

-   \or

-     \def\next##1##2##3##4##5##6##7%

-       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}{##7}}}%

-   \or

-     \def\next##1##2##3##4##5##6##7##8%

-       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}{##7}{##8}}}%

-   \or

-     \def\next##1##2##3##4##5##6##7##8##9%

-       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}{##7}{##8}{##9}}}% 

-   \else

-     \def\next%

-       {\message{illegal special: \string#1}}%

-   \fi

-   \next}

-

-%D The \type{{{...}}} are needed because we pass all those 

-%D arguments to the specials support macro. 

-

-\let\openspecialfile  = \relax

-\let\closespecialfile = \relax

-

-% %D This is some new, experimental code, used for testing some 

-% %D proposals of Laurent Siebenmann on behalf of the 

-% %D \kap{EMJ} discussionlist. 

-% 

-% \newif\ifexternalspecials  \externalspecialsfalse

-% \newif\ifspecialstatus     \specialstatustrue

-% 

-% \newwrite\specialfile

-% 

-% \def\openspecialfile%

-%   {\immediate\openout\specialfile=\jobname.etc\relax}

-% 

-% \def\closespecialfile%

-%   {\immediate\closeout\specialfile}

-% 

-% \let\internalspecial=\special

-% 

-% \def\externalspecial#1%

-%   {\internalspecial{}%

-%    \immediate\write\specialfile{\currentspecialdriver\space: #1}}

-% 

-% \def\doinstallspecial[#1][#2][#3]%

-%   {\setvalue{\@@specexc@@\string#1}{}%

-%    \setvalue{\@@speclst@@\string#1}{}%

-%    \setvalue{\@@speccat@@\string#1}{#2}%

-%    \setvalue{\@@specarg@@\string#1}{#3}%

-%    \addtocommalist{\string#1}\@@allspecials

-%    \def#1{\executespecial#1}}

-% 

-% \def\resetspecials%

-%   {\def\docommando##1%

-%      {\setvalue{\@@specexc@@##1}{}%

-%       \setvalue{\@@speclst@@##1}{}}%

-%    \processcommacommand[\@@allspecials]\docommando

-%    \showmessage{\m!specials}{3}{\preloadedspecials}}

-% 

-% \def\executespecials#1#2%

-%   {\edef\supportedspecials{\getvalue{\@@speclst@@\string#1}}%

-%    \def\doonespecial##1%

-%      {\doifdefined{##1\string#1}

-%         {\def\currentspecialdriver{##1}%

-%          \getvalue{##1\string#1}#2\relax}}%

-%    \ifexternalspecials

-%      \let\special=\externalspecial

-%      \doifelse{\supportedspecials}{}

-%        {\ifspecialstatus

-%           \immediate\write\specialfile{}%

-%           \immediate\write\specialfile{skipping  : \string#1}

-%           \immediate\write\specialfile{}%

-%         \fi}

-%        {\ifspecialstatus

-%           \immediate\write\specialfile{}%

-%           \immediate\write\specialfile{executing : \string#1}%

-%           \immediate\write\specialfile{supported : \supportedspecials}%

-%         \fi

-%         \immediate\write\specialfile{}%

-%         \processcommacommand[\supportedspecials]\doonespecial}%

-%    \else

-%      \let\special=\internalspecial

-%      \doifelse{\getvalue{\@@speccat@@\string#1}}{or}

-%        {\doonespecial{\getvalue{\@@specexc@@\string#1}}}

-%        {\processcommacommand[\supportedspecials]\doonespecial}%

-%    \fi}

-% 

-% \def\definespecial#1%

-%   {\ifx#1\undefined

-%      \showmessage{\m!specials}{4}{\string#1}%

-%      \def\next%

-%        {\def\@@illegalspecial@@}%

-%    \else

-%      \def\next%

-%        {\edef\@@newspeclst@@{\getvalue{\@@speclst@@\string#1}}%

-%         \addtocommalist{\currentspecial}\@@newspeclst@@

-%         \setevalue{\@@speclst@@\string#1}{\@@newspeclst@@}%

-%         \setevalue{\@@specexc@@\string#1}{\currentspecial}%

-%         \setvalue{\currentspecial\string#1}}%

-%    \fi

-%    \next}

-% 

-% %D So far for the experiment. 

-

-\protect

-

-%D The following libraries are defined. Two postscript

-%D drivers are supported, as well as two mechanisms for

-%D interactive texts.

-%D

-%D \startregelcorrectie

-%D \starttabel[|l|l|l|l|l|]

-%D \HL

-%D \NC \bf file             \NC

-%D     \bf name             \NC

-%D     \bf calls            \NC

-%D     \bf support          \NC

-%D     \bf program / driver \NC\SR

-%D \HL

-%D \NC \tttf spec-tex       \NC

-%D     \tttf tex            \NC

-%D                          \NC

-%D     Generic \TEX\ (\DVI) \NC

-%D     (default)            \NC\FR

-%D \NC \tttf spec-ps        \NC

-%D     \tttf postscript     \NC

-%D                          \NC

-%D     Adobe PostScript     \NC

-%D     (default)            \NC\MR

-%D \NC \tttf spec-tr        \NC

-%D     \tttf rokicky        \NC

-%D     \tttf postscript     \NC

-%D     Thomas Rokicky       \NC

-%D     (dvips)              \NC\MR

-%D \NC \tttf spec-yy        \NC

-%D     \tttf yandy          \NC

-%D     \tttf postscript     \NC

-%D     YandY                \NC

-%D     (dvipsone, dviwindo) \NC\MR

-%D \NC \tttf spec-pdf       \NC

-%D     \tttf pdf            \NC

-%D                          \NC

-%D     Adobe PDF V2.1       \NC

-%D     (Acrobat)            \NC\MR

-%D \NC \tttf spec-win       \NC

-%D     \tttf dviwindo       \NC

-%D     YandY                \NC

-%D     (dviwindo)           \NC\MR

-%D \NC \tttf spec-1p0       \NC

-%D     \tttf pdf            \NC

-%D                          \NC

-%D     Adobe PDF V 1.0      \NC

-%D     (Acrobat)            \NC\MR

-%D \NC \tttf spec-2p0       \NC

-%D     \tttf pdf            \NC

-%D                          \NC

-%D     Adobe PDF V 2.0      \NC

-%D     (Acrobat)            \NC\MR

-%D \NC \tttf spec-htm       \NC

-%D     \tttf html           \NC

-%D                          \NC

-%D     HTML V 2.0           \NC

-%D     (dvips)              \NC\LR

-%D \HL

-%D \stoptabel

-%D \stopregelcorrectie

-

-%D \macros

-%D   {dostartgraymode,dostopgraymode,

-%D    dostartrgbcolormode,dostartcmykcolormode,dostartgraycolormode,dostopcolormode}

-%D   {}

-%D

-%D We start with the installation of color and grayscale

-%D specials. The values are in the range 0..1 (e.g. 0.25).

-%D

-%D \starttypen

-%D \dostartgraymode      {gray} ... \dostopgraymode

-%D \dostartrgbcolormode  {red} {green} {blue} ... \dostopcolormode

-%D \dostartcmykcolormode {cyan} {magenta} {yellow} {black} ... \dostopcolormode

-%D \dostartgraycolormode {gray} ... \dostopcolormode

-%D \stoptypen

-%D

-%D Because we can expect conflicts between drivers, we

-%D implement them as category \type{or}. In previous versions

-%D of \DVIPSONE\ the use of their color||specials did not

-%D interfere with the PostScript ones, but recent versions do.

-

-\installspecial [\dostartgraymode]      [or] [1]

-\installspecial [\dostopgraymode]       [or] [0]

-

-\installspecial [\dostartrgbcolormode]  [or] [3]

-\installspecial [\dostartcmykcolormode] [or] [4]

-\installspecial [\dostartgraycolormode] [or] [1]

-\installspecial [\dostopcolormode]      [or] [0]

-

-%D \macros

-%D   {doinsertfile}

-%D   {}

-%D

-%D Probably the most problematic special is the following

-%D one. Because we want to be able to support different

-%D schemes, we pass a lot of data to it.

-%D

-%D \starttypen

-%D \doinsertfile {type,method} {file} 

-%D               {xscale} {yscale} {x} {y} {w} {h} 

-%D               {options}

-%D \stoptypen

-%D

-%D The scale is given percents, the other values are base 

-%D points.

-%D

-%D The special is implemented as \type{or}. Because

-%D \DVIPSONE\ understands them all, a chain of alternatives

-%D would generate multiple courrences of the same

-%D illustration.

-%D

-%D When option 1 is passed, the viewers is asked to present a

-%D preview, like the first frame of a movie. 

-

-\installspecial [\doinsertfile] [or] [9]

-

-%D \macros

-%D   {dostartrotation,

-%D    dostoprotation}

-%D   {}

-%D

-%D We support rotation with the special:

-%D

-%D \starttypen

-%D \dostartrotation {angle} ... \dostoprotation

-%D \stoptypen

-%D

-%D For the moment these specials are installed as

-%D category \type{or}.

-

-\installspecial [\dostartrotation] [or] [1]

-\installspecial [\dostoprotation]  [or] [0]

-

-%D \macros

-%D   {dostartscaling,

-%D    dostopscaling}

-%D   {}

-%D

-%D Scaling is also supported:

-%D

-%D \starttypen

-%D \dostartscaling {x} {y} ... \dostopscaling

-%D \stoptypen

-%D

-%D Like the previous one, these specials are of category 

-%D \type{or}.

-

-\installspecial [\dostartscaling] [or] [2]

-\installspecial [\dostopscaling]  [or] [0]

-

-%D \macros

-%D   {dostartmirroring,

-%D    dostopmirroring}

-%D   {}

-%D

-%D And indeed, mirroring is there too:

-%D

-%D \starttypen

-%D \dostartmirroring {x} {y} ... \dostopmirroring

-%D \stoptypen

-%D

-%D Again these specials are installed as category \type{or}.

-

-\installspecial [\dostartmirroring] [or] [0]

-\installspecial [\dostopmirroring]  [or] [0]

-

-%D \macros

-%D   {dostartnegative,

-%D    dostopnegative}

-%D   {}

-%D

-%D When producing output for an image setter, negating the 

-%D page comes into view. Here are the tools:

-

-\installspecial [\dostartnegative] [or] [0]

-\installspecial [\dostopnegative]  [or] [0]

-

-%D \macros

-%D   {doselectfirstpaperbin,

-%D    doselectsecondpaperbin}

-%D   {}

-%D

-%D Here are some very printer||specific ones. No further

-%D comment.

-

-\installspecial [\doselectfirstpaperbin]  [or]  [0]

-\installspecial [\doselectsecondpaperbin] [or]  [0]

-

-%D \macros

-%D   {doovalbox}

-%D   {}

-%D

-%D When we look at the implementation, this is a complicated

-%D one. There are seven arguments.

-%D

-%D \starttypen

-%D \doovalbox {w} {h} {d} {linewidth} {radius} {stroke} {fill}

-%D \stoptypen

-%D

-%D This command has to return a \type{\vbox} which can be used

-%D to lay over another one (with text). The radius is in

-%D degrees, the stroke and fill are~\type{1} (true) of~\type{0}

-%D (false). 

-

-\installspecial [\doovalbox] [or] [7]

-

-%D \macros

-%D   {dosetupidentity}

-%D   {}

-%D

-%D We can declare some characteristics of the document with

-%D

-%D \starttypen 

-%D \dosetupidentity {title} {subject} {author} {creator} {date} 

-%D \stoptypen

-%D

-%D All data is in string format. 

-

-\installspecial [\dosetupidentity] [and] [5]

-

-%D \macros

-%D   {dosetuppaper}

-%D   {}

-%D

-%D This special can be used to tell the driver what page size

-%D to use. The special takes three arguments. 

-%D

-%D \starttypen

-%D \dosetuppaper {type} {width} {height}

-%D \stoptypen

-%D

-%D The type is one of the common identifiers, like A4, A5 or 

-%D B2. 

-

-\installspecial [\dosetuppaper] [and] [3]

-

-%D \macros

-%D   {dosetupprinter}

-%D   {}

-%D

-%D Some drivers enable the user to specify the paper type 

-%D used and/or page dimensions to be taken into account. 

-%D

-%D \starttypen

-%D \dosetupprinter {type} {hoffset} {voffset} {width} {height}

-%D \stoptypen

-%D

-%D The first argument is one of \type{letter}, \type{legal}, 

-%D \type{A4}, \type{A5} etc. The dimensions are in 

-%D basepoints. 

-

-\installspecial [\dosetupprinter] [and] [5]

-

-%D \macros

-%D   {dosetuppage,

-%D    dosetupinteraction,

-%D    dosetupscreen}

-%D   {}

-%D

-%D Here come some obscure interactive commands. Probably the

-%D specs will change with the development of the macros that

-%D use them.

-%D

-%D The first ones can be used to set up the interaction.

-%D

-%D \starttypen

-%D \dosetupinteraction

-%D \stoptypen

-%D

-%D Normally this command does nothing but giving a message

-%D that some scheme is supported. Postscript prolog files

-%D can best be loaded by the printer driver program.

-%D

-%D The second one sets up the screen. It takes three

-%D arguments:

-%D

-%D \starttypen

-%D \dosetupscreen {hoffset} {voffset} {width} {height} {options}

-%D \stoptypen

-%D

-%D The first four arguments are in scaled points. Option~1 

-%D results in a full screen launch.

-

-\installspecial [\dosetupinteraction] [and] [0]

-\installspecial [\dosetupscreen]      [and] [5]

-

-%D \macros

-%D   {dostarthide,

-%D    dostophide}

-%D   {}

-%D

-%D Not every part of the screen is suitable for paper. Menus

-%D for instance have no meaning on an non||interactive medium.

-%D These elements are hidden by means of:

-%D

-%D \starttypen

-%D \dostarthide

-%D \dostophide

-%D \stoptypen

-

-\installspecial [\dostarthide]        [or]  [0]

-\installspecial [\dostophide]         [or]  [0]

-

-%D \macros

-%D   {dostartgotolocation, dostopgotolocation,

-%D    dostartgotorealpage, dostopgotorealpage}

-%D   {}

-%D

-%D The interactive real work is done by the following four

-%D specials. The reason for providing the first one with both

-%D a label and a number, is a result of the quite poor

-%D implementation of \type{pdfmarks} in version 1.0 of

-%D Acrobat. Because only pagenumbers were supported as

-%D destination, we had to provide both labels (\DVIWINDO) and

-%D pagenumbers (\PDF). Some drivers use start stop pairs. 

-%D

-%D \starttypen

-%D \dostartgotolocation {w} {h} {url} {file} {label} {page}

-%D \dostartgotorealpage {w} {h} {url} {file}         {page}

-%D \stoptypen

-%D

-%D Their counterparts are:

-%D

-%D \starttypen

-%D \dostopgotolocation  

-%D \dostopgotorealpage  

-%D \stoptypen

-%D

-%D The internal alternative is used for system||generated

-%D links, the external one for user||generated links. The 

-%D Uniform Resource Locator can be used to let the reader 

-%D surf the net. 

-

-\installspecial [\dostartgotolocation] [and] [6]

-\installspecial [\dostopgotolocation]  [and] [0]

-\installspecial [\dostartgotorealpage] [and] [5]

-\installspecial [\dostopgotorealpage]  [and] [0]

-

-%D \macros

-%D  {dostartgotoJS, doflushJSpreamble}

-%D   

-%D

-%D Rather special is the option to include and execute 

-%D JavaScript code. This is a typical \PDF\ option.

-%D

-%D \starttypen

-%D \dostartgotoJS {w} {h} {script}

-%D \stoptypen

-%D

-%D This not so standard \TEX\ feature should be used with 

-%D care. Preamble scripts are flushed by

-%D

-%D \doflushJSpreamble {script}

-

-\installspecial [\dostartgotoJS]    [and] [3]

-\installspecial [\dostopgotoJS]     [and] [0]

-\installspecial [\doflushJSpreamble][and] [1]

-

-%D \macros

-%D   {dostartthisislocation, dostopthisislocation,

-%D    dostartthisisrealpage, dostopthisisrealpage}

-%D   {}

-%D

-%D The opposite commands of \type{\dogotosomething} have only

-%D one argument:

-%D

-%D \starttypen

-%D \dostartthisislocation {label}

-%D \dostartthisisrealpage {page}

-%D \stoptypen

-%D

-%D These commands are accompanied by: 

-%D

-%D \starttypen

-%D \dostopthisislocation  

-%D \dostopthisisrealpage 

-%D \stoptypen

-%D

-%D As with all interactive commands's they are installed as

-%D \type{and} category specials.

-

-\installspecial [\dostartthisislocation] [and] [1]

-\installspecial [\dostopthisislocation]  [and] [0]

-\installspecial [\dostartthisisrealpage] [and] [1]

-\installspecial [\dostopthisisrealpage]  [and] [0]

-

-%D \macros

-%D   {dostartexecutecommand, dostopexecutecommand}

-%D   {}

-%D

-%D The actual behavior of the next pair of commands depends 

-%D much on the viewing engine. Therefore one cannot depend 

-%D too much on their support. 

-%D

-%D \starttypen

-%D \dostartexecutecommand {w} {h} {command} {options} 

-%D \stoptypen

-%D

-%D

-%D The next commands are supported: 

-%D

-%D \startregelcorrectie\steluitlijnenin[midden]\leavevmode

-%D \starttabel[|l|l|] 

-%D \HL

-%D \NC \bf command  \NC \bf action                  \NC\SR 

-%D \HL

-%D \NC first        \NC go to the first page        \NC\FR

-%D \NC previous     \NC go to the previous page     \NC\MR

-%D \NC next         \NC go to the next page         \NC\MR

-%D \NC last         \NC go to the last page         \NC\MR

-%D \NC backward     \NC go back to the  link list   \NC\MR

-%D \NC forward      \NC go forward in the link list \NC\MR

-%D \NC print        \NC enter print mode            \NC\MR

-%D \NC exit         \NC exit viewer                 \NC\MR

-%D \NC close        \NC close document              \NC\MR

-%D \NC enter        \NC enter viewer                \NC\MR

-%D \NC help         \NC show help on the viewer     \NC\LR

-%D \HL

-%D \stoptabel

-%D \stopregelcorrectie

-%D

-%D There are no options yet. Options are to be passed as a 

-%D comma separated list of assignments.

-

-\installspecial [\dostartexecutecommand] [and] [4]

-\installspecial [\dostopexecutecommand]  [and] [0]

-

-%D \macros

-%D   {dostartobject, 

-%D    dostopobject,

-%D    doinsertobject}

-%D

-%D Reuse of object can reduce the output filesize 

-%D considerably. Reusable objects are implemented with: 

-%D

-%D \starttypen

-%D \dostartobject{name}{width}{height}{depth}

-%D some typeset material

-%D \dostopobject

-%D \stoptypen

-%D

-%D \starttypen

-%D \doinsertobject{name}

-%D \stoptypen

-%D

-%D The savings can be huge in interactive texts. 

-

-\installspecial [\dostartobject]  [or] [4]

-\installspecial [\dostopobject]   [or] [0]

-\installspecial [\doinsertobject] [or] [1]

-

-% %D \macros

-% %D   {dogetobjectreference} 

-% %D

-% %D For very special purposes, one can ask for the internal 

-% %D reference to the object. Beware!

-% 

-% \installspecial [\dogetobjectreference] [or] [2]

-% 

-% %D The first argument is the name, the second a macro that 

-% %D gets the assiciated value.

-

-%D \macros

-%D   {dostartrunprogram, dostoprunprogram,

-%D    dostartgotoprofile, dostopgotoprofile,

-%D    dobeginofprofile,

-%D    doendofprofile}

-%D   {}

-%D

-%D These specials are still experimental. They are not yet

-%D supported by the programs the way they should be.

-%D

-%D {\em --- still undocumented ---}

-

-\installspecial [\dostartrunprogram]  [and] [3]

-\installspecial [\dostoprunprogram]   [and] [0]

-\installspecial [\dostartgotoprofile] [and] [3]

-\installspecial [\dostopgotoprofile]  [and] [0]

-\installspecial [\dobeginofprofile]   [and] [4]

-\installspecial [\doendofprofile]     [and] [0]

-

-%D \macros

-%D   {doinsertbookmark}

-%D 

-%D Bookmarks, that is viewer generated tables of contents, are

-%D a strange phenomena, mainly because \TEX\ can provide

-%D whatever kind of table in much better quality. 

-

-\installspecial [\doinsertbookmark] [and] [5]

-

-%D This special is called as:

-%D 

-%D \starttypen

-%D \doinstallbookmark {level} {nofsubentries} {text} {page} {open}

-%D \stoptypen

-%D

-%D This definition is very \PDF\ oriented, so for more 

-%D information we kindly refer to the \PDF\ manuals. 

-

-%D \macros

-%D   {dosetpagetransition}

-%D

-%D In presentations, fancy page transitions can, at least for a

-%D short moment, let the audience focus at the screen. Like the

-%D previous one, this special is very \PDF. 

-%D

-%D \starttypen

-%D \dosetpagetransition{dissolve}

-%D \stoptypen

-%D

-%D Transitions have symbolic names, like dissolve, box, split,

-%D blinds, wipe and glitter.

-

-\installspecial [\dosetpagetransition] [or] [1]

-

-%D So far for the installation. Finally we preload our

-%D favorite set of specials.

-

-\usespecials[ps,yy,win,pdf]

-

-%D One can overrule this by for instance

-%D 

-%D \starttypen

-%D \usespecials[reset,ps,tr,pdf]

-%D \stoptypen

-

-\endinput

+%D \module
+%D   [       file=spec-ini,
+%D        version=1996.01.25,
+%D          title=\CONTEXT\ Special Macros,
+%D       subtitle=Initialization,
+%D         author=Hans Hagen,
+%D           date=\currentdate,
+%D      copyright={PRAGMA / Hans Hagen \& Ton Otten}]
+%C
+%C This module is part of the \CONTEXT\ macro||package and is
+%C therefore copyrighted by \PRAGMA. Non||commercial use is 
+%C granted. 
+
+%D Specials are \TEX's channel to the outside world. They make
+%D \TEX\ even more platform independant and permit easy
+%D adaption to new developments. One major drawback of specials
+%D is that they have to be supported by printer drivers. We've
+%D tried to overcome this problem by implementinmg specials as
+%D a sort of drivers themselves.
+
+\writestatus{loading}{Context Special Macros / Initialization}
+
+\unprotect
+
+\startmessages  dutch  library: specials
+  title: specials
+      1: -- geladen
+      2: verdere nesting is niet toegestaan --
+      3: -- gereset
+      4: commando -- bestaat niet
+      5: definitiefile -- wordt geladen
+      6: nesting is niet toegestaan
+      7: onbekende driver --
+\stopmessages
+
+\startmessages  english  library: specials
+  title: specials
+      1: -- loaded
+      2: no deeper nesting is permitted --
+      3: -- is reset
+      4: command -- does not exist
+      5: loading definition file --
+      6: nesting is not permitted
+      7: unknown driver --
+\stopmessages
+
+\startmessages  german  library: specials
+  title: spezielles
+      1: -- geladen
+      2: keine tiefere Verschachtelung erlaubt --
+      3: -- ist zurueckgesetzt
+      4: Befehl -- existiert nicht
+      5: lade Definitionsdatei --
+      6: Verschachtelung nicht erlaubt
+      7: unbekante Driver --
+\stopmessages
+
+\startmessages  dutch  library: interactions
+     21: -- code tussengevoegd
+\stopmessages
+
+\startmessages  english  library: interactions
+     21: -- code inserted
+\stopmessages
+
+\startmessages  german  library: interactions
+     21: -- Code eingefuegt
+\stopmessages
+
+%D \macros 
+%D   {everyresetspecials}
+%D
+%D Now what will this one do? We'll see in a few lines. 
+
+\newevery \everyresetspecials \relax
+
+%D \macros
+%D   {jobsuffix}
+%D
+%D By default, \TEX\ produces \DVI\ files which can be 
+%D converted to other filetypes. Sometimes it is handy to 
+%D know what the target file will be. In other driver 
+%D modules we wil set \type {\jobsuffix} to \type {pdf}.  
+
+\def\jobsuffix{dvi}
+
+\appendtoks \def\jobsuffix{dvi} \to \everyresetspecials
+
+%D A rather fundamental difference between special and direct
+%D settings is that the latter don't interfere with typesetting
+%D but must be set before the first shipout, while the specials
+%D must be packaged in the shipped out box in such a way that
+%D they don't interfere. 
+
+\newif\ifspecialbasedsettings \specialbasedsettingstrue
+
+\appendtoks \specialbasedsettingstrue \to \everyresetspecials
+
+%D Because there is no standardization in the use of specials,
+%D more than one driver or program can be supported. The
+%D specials are grouped in libraries. Some of these are
+%D general, such as the \type{postscript} library, some are
+%D tuned to a special kind of program, like the \type{pdf}
+%D ones, and some support a specific driver, as we can see in
+%D the \type{yandy} library. A library is build with the
+%D commands:
+%D
+%D \starttypen
+%D \startspecials[name][inheritance]
+%D
+%D \definespecial\none{...}
+%D \definespecial\onlyone#1{...}
+%D \definespecial\alot#1#2#3#4{...}
+%D
+%D \stopspecials
+%D \stoptypen
+%D
+%D Because drivers can have overlap in low level macros, a 
+%D mechanism of inheritance is implemented. The libraries 
+%D defined as second argument are loaded first. 
+%D
+%D Every special has to be predefined first. We  do this with
+%D the command:
+%D
+%D \starttypen
+%D \installspecial [\none]    [and] [0]
+%D \installspecial [\onlyone] [and] [1]
+%D \installspecial [\alot]    [or]  [4]
+%D \stoptypen
+%D
+%D This means as much as: there is a special names
+%D \type{\none} which has no arguments and has more than one
+%D appearance. The special \type{\alot} on the other hand has
+%D four arguments and is only defined once. Every instance in
+%D the libraries of a special of category \type{and} is
+%D executed when called upon, but only one special of
+%D category \type{or} can be active. Most of the
+%D \type{postscript}||specials are of category \type{or},
+%D because they tend to interfere with driver specific ones.
+%D The interactive specials of \type{dviwindo} and \type{pdf}
+%D are an example of specials that can be called both.
+%D
+%D A library is defined in a file with the name
+%D \type{spec-...}. We load a library with the command:
+%D
+%D \starttypen
+%D \usespecials [list]
+%D \stoptypen
+%D
+%D where the list can contain one or more file tags, the
+%D \type{...} in the filename. The keyword \type{reset}
+%D resets all loaded specials. This is equivalent to
+%D \type{\resetspecials}.
+
+%D Although a mechanism of nesting can be implemented, we
+%D prefer to use a inheritance mechanism as mentioned. Calls
+%D upon \type{\usespecials} within a \type{\startspecials}
+%D would lead to confusion and errors.
+
+\newif\ifinheritspecials
+
+%D We define some local constants and variables. They look a
+%D bit horrible but we don't want conflicts.
+
+\def\@@specfil@@{@@specfil@@}
+\def\@@speclst@@{@@speclst@@}
+\def\@@speccat@@{@@speccat@@}
+\def\@@specarg@@{@@specarg@@}
+\def\@@specexc@@{@@specexc@@}
+
+\let\currentspecial    =\empty
+\let\currentspecialfile=\empty
+\let\preloadedspecials =\empty
+
+%D \macros
+%D   {preloadspecials}
+%D   {}
+%D
+%D The following command can be used to show the loaded list
+%D of specials.
+
+\def\preloadspecials%
+  {\doifsomething{\preloadedspecials}
+     {\showmessage{\m!specials}{1}{\preloadedspecials}}}
+
+%D \macros
+%D   {startspecials}
+%D   {}
+%D
+%D Every library has a unique name, which is given as the first
+%D argument to \type{\startspecials}. When another library is
+%D defined with the same name, previous specials can be
+%D overruled. The name may differ from the file||tag.
+%D
+%D The optional second argument can consist of a list of
+%D libraries that are to be loaded first. 
+
+% to fuzzy and error prone 
+%
+% \def\dostartspecials[#1][#2]%
+%   {\let\mainspecialfile=\currentspecialfile
+%    \doifelsenothing{#2}
+%      {\inheritspecialsfalse}
+%      {\ifinheritspecials
+%         \showmessage{\m!specials}{2}{(#2)}%
+%       \else
+%         \inheritspecialstrue
+%         \processcommalist[#2]\dousespecials
+%         \inheritspecialsfalse
+%       \fi}%
+%    \doifelsenothing{#1}
+%      {\let\currentspecial\s!unknown}
+%      {\def\currentspecial{#1}}%
+%    \let\currentspecialfile=\mainspecialfile
+%    \setevalue{\@@specfil@@\currentspecial}{\currentspecialfile}%
+%    \unprotect
+%    \addtocommalist{\currentspecial}\preloadedspecials}
+% 
+% \def\startspecials%
+%   {\dodoubleempty\dostartspecials}
+% 
+% \def\stopspecials%
+%   {\def\currentspecial{}%
+%    \protect}
+
+\def\dostartspecials[#1][#2]%
+  {\doifsomething{#2}
+     {\processcommalist[#2]\dousespecials}%
+   \doifelsenothing{#1}
+     {\let\currentspecial\s!unknown}
+     {\def\currentspecial{#1}}%
+   \unprotect
+   \addtocommalist{\currentspecial}\preloadedspecials}
+
+\def\startspecials%
+  {\pushmacro\currentspecial
+   \dodoubleempty\dostartspecials}
+
+\def\stopspecials%
+  {\popmacro\currentspecial
+   \protect}
+ 
+%D \macros
+%D   {installspecial,
+%D    resetspecials}
+%D   {}
+%D
+%D We have to install specials before we can define and use
+%D them. The command itself is defined as a call to another
+%D command that executes one or more user||defined specials,
+%D depending of it's category: \type{or} versus \type{and}.
+%D
+%D The command \type{\installspecial} takes three
+%D (non||optional) arguments: the name of the command, the
+%D category it belongs to and the number of arguments it
+%D takes.
+%D
+%D With \type{\resetspecials} we can unload the predefined
+%D specials. Special reset actions |<|look in \type{spec-mis}
+%D for an example|>| can be assigned to the token register 
+%D \type{\everyresetspecials}.
+
+\let\@@allspecials=\empty
+
+\def\doinstallspecial[#1][#2][#3]%
+  {\setvalue{\@@speclst@@\string#1}{}%
+   \setvalue{\@@speccat@@\string#1}{#2}%
+   \setvalue{\@@specarg@@\string#1}{#3}%
+   \addtocommalist{\string#1}\@@allspecials
+   \def#1{\executespecial#1}}
+
+\def\installspecial%
+  {\dotripleargument\doinstallspecial}
+
+\def\resetspecials%
+  {\the\everyresetspecials
+   \def\docommando##1%
+     {\letvalue{\@@speclst@@##1}\empty}%
+   \processcommacommand[\@@allspecials]\docommando
+   \ifx\preloadedspecials\empty \else
+     \showmessage{\m!specials}{3}{\preloadedspecials}%
+     \let\preloadedspecials\empty
+   \fi}
+
+%D \macros
+%D   {definespecial}
+%D
+%D The command \type{\definespecial} take the place of
+%D \type{\def} in the definition of a special. Just to be
+%D sure, we first check if the command is permitted, i.e.
+%D installed. If not, we give a warning and gobble the
+%D illegal command in an quite elegant way.
+%D
+%D If the command can be combined (\type{and}) with others,
+%D we append it to a list, otherwise (\type{or}) it becomes
+%D the only item in the list.
+
+\def\definespecial#1%
+  {\ifx#1\undefined
+     \showmessage{\m!specials}{4}{\string#1}%
+     \def\next%
+       {\def\@@illegalspecial@@}%
+   \else
+     \def\next%
+       {\doifelse{\getvalue{\@@speccat@@\string#1}}{or}
+          {\edef\@@newspeclst@@{\currentspecial}}
+          {\edef\@@newspeclst@@{\getvalue{\@@speclst@@\string#1}}%
+           \addtocommalist{\currentspecial}\@@newspeclst@@}%
+        \setevalue{\@@speclst@@\string#1}{\@@newspeclst@@}%
+        \setvalue{\currentspecial\string#1}}%
+   \fi
+   \next}
+
+%D \macros
+%D   {usespecials}
+%D   {}
+%D
+%D We use \type{\usespecials} to load a specific library.
+%D This command is only permitted outside de definition part.
+
+\def\dousespecials#1%
+  {\doifelse{#1}{\v!reset}
+     {\resetspecials}
+     {\doifdefinedelse{\@@specfil@@#1}
+        {\edef\currentspecialfile{\getvalue{\@@specfil@@#1}}}
+        {\edef\currentspecialfile{#1}}%
+      \makeshortfilename[\f!specialprefix\currentspecialfile]%
+      \showmessage{\m!specials}{5}{\currentspecialfile}%
+      \startreadingfile
+      \readsysfile{\shortfilename}{}{}%
+      \stopreadingfile
+      \showmessage{\m!specials}{1}{\preloadedspecials}}}
+
+\def\usespecials[#1]%
+  {\doifelsenothing{\currentspecial}
+     {\processcommalist[#1]\dousespecials}
+     {\showmessage{\m!specials}{6}{}}}
+
+%D \macros
+%D   {executespecials}
+%D   {}
+%D
+%D The command \type{\executespecials} is used to execute the
+%D defined specials. Once a special is installed, the special
+%D itself calls for this command, so it's not needed outside
+%D this module. One can use it if wanted.
+%D 
+%D A former implementation grouped the execution. Recent 
+%D additions however |<|like the specials that implement object 
+%D handling|>| asked for non||grouped execution. 
+
+\def\executespecials#1#2%
+  {\def\doonespecial##1%
+     {\getvalue{##1\string#1}#2\relax}%
+   \processcommacommand
+     [\getvalue{\@@speclst@@\string#1}]\doonespecial}
+
+\def\executespecial#1%
+  {\expandafter\ifcase\getvalue{\@@specarg@@\string#1}\relax
+     \def\next%
+       {\executespecials#1{}}%
+   \or
+     \def\next##1%
+       {\executespecials#1{{##1}}}%
+   \or
+     \def\next##1##2%
+       {\executespecials#1{{##1}{##2}}}%
+   \or
+     \def\next##1##2##3%
+       {\executespecials#1{{##1}{##2}{##3}}}%
+   \or
+     \def\next##1##2##3##4%
+       {\executespecials#1{{##1}{##2}{##3}{##4}}}%
+   \or
+     \def\next##1##2##3##4##5%
+       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}}}%
+   \or
+     \def\next##1##2##3##4##5##6%
+       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}}}%
+   \or
+     \def\next##1##2##3##4##5##6##7%
+       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}{##7}}}%
+   \or
+     \def\next##1##2##3##4##5##6##7##8%
+       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}{##7}{##8}}}%
+   \or
+     \def\next##1##2##3##4##5##6##7##8##9%
+       {\executespecials#1{{##1}{##2}{##3}{##4}{##5}{##6}{##7}{##8}{##9}}}% 
+   \else
+     \def\next%
+       {\message{illegal special: \string#1}}%
+   \fi
+   \next}
+
+%D The \type{{{...}}} are needed because we pass all those 
+%D arguments to the specials support macro. 
+
+\let\openspecialfile  = \relax
+\let\closespecialfile = \relax
+
+%D \macros
+%D   {doifspecialavailableelse}
+%D 
+%D For testing purposes (this was first needed when object 
+%D support was implemented) we have: 
+%D 
+%D \starttypen
+%D \doifspecialavailableelse\specialcommand{true}{false}
+%D \stoptypen
+%D 
+%D e.g: 
+%D 
+%D \starttypen
+%D \doifspecialavailableelse\doinsertobject{...}{...}
+%D \stoptypen
+
+\def\doifspecialavailableelse#1#2#3%
+  {\doifelsevaluenothing{\@@speclst@@\string#1}{#3}{#2}}
+
+% %D This is some new, experimental code, used for testing some 
+% %D proposals of Laurent Siebenmann on behalf of the 
+% %D \kap{EMJ} discussionlist. 
+% 
+% \newif\ifexternalspecials  \externalspecialsfalse
+% \newif\ifspecialstatus     \specialstatustrue
+% 
+% \newwrite\specialfile
+% 
+% \def\openspecialfile%
+%   {\immediate\openout\specialfile=\jobname.etc\relax}
+% 
+% \def\closespecialfile%
+%   {\immediate\closeout\specialfile}
+% 
+% \let\internalspecial=\special
+% 
+% \def\externalspecial#1%
+%   {\internalspecial{}%
+%    \immediate\write\specialfile{\currentspecialdriver\space: #1}}
+% 
+% \def\doinstallspecial[#1][#2][#3]%
+%   {\setvalue{\@@specexc@@\string#1}{}%
+%    \setvalue{\@@speclst@@\string#1}{}%
+%    \setvalue{\@@speccat@@\string#1}{#2}%
+%    \setvalue{\@@specarg@@\string#1}{#3}%
+%    \addtocommalist{\string#1}\@@allspecials
+%    \def#1{\executespecial#1}}
+% 
+% \def\resetspecials%
+%   {\def\docommando##1%
+%      {\setvalue{\@@specexc@@##1}{}%
+%       \setvalue{\@@speclst@@##1}{}}%
+%    \processcommacommand[\@@allspecials]\docommando
+%    \showmessage{\m!specials}{3}{\preloadedspecials}}
+% 
+% \def\executespecials#1#2%
+%   {\edef\supportedspecials{\getvalue{\@@speclst@@\string#1}}%
+%    \def\doonespecial##1%
+%      {\doifdefined{##1\string#1}
+%         {\def\currentspecialdriver{##1}%
+%          \getvalue{##1\string#1}#2\relax}}%
+%    \ifexternalspecials
+%      \let\special=\externalspecial
+%      \doifelse{\supportedspecials}{}
+%        {\ifspecialstatus
+%           \immediate\write\specialfile{}%
+%           \immediate\write\specialfile{skipping  : \string#1}
+%           \immediate\write\specialfile{}%
+%         \fi}
+%        {\ifspecialstatus
+%           \immediate\write\specialfile{}%
+%           \immediate\write\specialfile{executing : \string#1}%
+%           \immediate\write\specialfile{supported : \supportedspecials}%
+%         \fi
+%         \immediate\write\specialfile{}%
+%         \processcommacommand[\supportedspecials]\doonespecial}%
+%    \else
+%      \let\special=\internalspecial
+%      \doifelse{\getvalue{\@@speccat@@\string#1}}{or}
+%        {\doonespecial{\getvalue{\@@specexc@@\string#1}}}
+%        {\processcommacommand[\supportedspecials]\doonespecial}%
+%    \fi}
+% 
+% \def\definespecial#1%
+%   {\ifx#1\undefined
+%      \showmessage{\m!specials}{4}{\string#1}%
+%      \def\next%
+%        {\def\@@illegalspecial@@}%
+%    \else
+%      \def\next%
+%        {\edef\@@newspeclst@@{\getvalue{\@@speclst@@\string#1}}%
+%         \addtocommalist{\currentspecial}\@@newspeclst@@
+%         \setevalue{\@@speclst@@\string#1}{\@@newspeclst@@}%
+%         \setevalue{\@@specexc@@\string#1}{\currentspecial}%
+%         \setvalue{\currentspecial\string#1}}%
+%    \fi
+%    \next}
+% 
+% %D So far for the experiment. 
+
+%D The following libraries are defined. Two postscript
+%D drivers are supported, as well as two mechanisms for
+%D interactive texts.
+%D
+%D \startregelcorrectie
+%D \starttabel[|l|l|l|l|l|]
+%D \HL
+%D \NC \bf file             \NC
+%D     \bf name             \NC
+%D     \bf calls            \NC
+%D     \bf support          \NC
+%D     \bf program / driver \NC\SR
+%D \HL
+%D \NC \tttf spec-tex       \NC
+%D     \tttf tex            \NC
+%D                          \NC
+%D     Generic \TEX\ (\DVI) \NC
+%D     (default)            \NC\FR
+%D \NC \tttf spec-tpd       \NC
+%D     \tttf \PDF           \NC
+%D                          \NC
+%D     Han The Thanh        \NC
+%D     (pdftex)             \NC\MR
+%D \NC \tttf spec-ps        \NC
+%D     \tttf postscript     \NC
+%D                          \NC
+%D     Adobe PostScript     \NC
+%D     (default)            \NC\MR
+%D \NC \tttf spec-tr        \NC
+%D     \tttf rokicki        \NC
+%D     \tttf postscript     \NC
+%D     Thomas Rokicki       \NC
+%D     (dvips)              \NC\MR
+%D \NC \tttf spec-yy        \NC
+%D     \tttf yandy          \NC
+%D     \tttf postscript     \NC
+%D     YandY                \NC
+%D     (dvipsone, dviwindo) \NC\MR
+%D \NC \tttf spec-pdf       \NC
+%D     \tttf pdf            \NC
+%D                          \NC
+%D     Adobe PDF V2.1       \NC
+%D     (Acrobat)            \NC\MR
+%D \NC \tttf spec-win       \NC
+%D     \tttf dviwindo       \NC
+%D     YandY                \NC
+%D     (dviwindo)           \NC\MR
+%D \NC \tttf spec-1p0       \NC
+%D     \tttf pdf            \NC
+%D                          \NC
+%D     Adobe PDF V 1.0      \NC
+%D     (Acrobat)            \NC\MR
+%D \NC \tttf spec-2p0       \NC
+%D     \tttf pdf            \NC
+%D                          \NC
+%D     Adobe PDF V 2.0      \NC
+%D     (Acrobat)            \NC\MR
+%D \NC \tttf spec-htm       \NC
+%D     \tttf html           \NC
+%D                          \NC
+%D     HTML V 2.0           \NC
+%D     (dvips)              \NC\LR
+%D \HL
+%D \stoptabel
+%D \stopregelcorrectie
+
+%D \macros
+%D   {dostartgraymode,dostopgraymode,
+%D    dostartrgbcolormode,dostartcmykcolormode,dostartgraycolormode,dostopcolormode}
+%D   {}
+%D
+%D We start with the installation of color and grayscale
+%D specials. The values are in the range 0..1 (e.g. 0.25).
+%D
+%D \starttypen
+%D \dostartgraymode      {gray} ... \dostopgraymode
+%D \dostartrgbcolormode  {red} {green} {blue} ... \dostopcolormode
+%D \dostartcmykcolormode {cyan} {magenta} {yellow} {black} ... \dostopcolormode
+%D \dostartgraycolormode {gray} ... \dostopcolormode
+%D \stoptypen
+%D
+%D Because we can expect conflicts between drivers, we
+%D implement them as category \type{or}. In previous versions
+%D of \DVIPSONE\ the use of their color||specials did not
+%D interfere with the PostScript ones, but recent versions do.
+
+\installspecial [\dostartgraymode]      [or] [1]
+\installspecial [\dostopgraymode]       [or] [0]
+
+\installspecial [\dostartrgbcolormode]  [or] [3]
+\installspecial [\dostartcmykcolormode] [or] [4]
+\installspecial [\dostartgraycolormode] [or] [1]
+\installspecial [\dostopcolormode]      [or] [0]
+
+%D \macros
+%D   {doinsertfile}
+%D   {}
+%D
+%D Probably the most problematic special is the following
+%D one. Because we want to be able to support different
+%D schemes, we pass a lot of data to it.
+%D
+%D \starttypen
+%D \doinsertfile {type,method} {file,label} 
+%D               {xscale} {yscale} {x} {y} {w} {h} 
+%D               {options}
+%D \stoptypen
+%D
+%D The scale is given percents, the other values are base 
+%D points.
+%D
+%D The special is implemented as \type{or}. Because
+%D \DVIPSONE\ understands them all, a chain of alternatives
+%D would generate multiple courrences of the same
+%D illustration.
+%D
+%D When option 1 is passed, the viewers is asked to present a
+%D preview, like the first frame of a movie. 
+
+\installspecial [\doinsertfile] [or] [9]
+
+%D \macros
+%D   {dostartrotation,
+%D    dostoprotation}
+%D   {}
+%D
+%D We support rotation with the special:
+%D
+%D \starttypen
+%D \dostartrotation {angle} ... \dostoprotation
+%D \stoptypen
+%D
+%D For the moment these specials are installed as
+%D category \type{or}.
+
+\installspecial [\dostartrotation] [or] [1]
+\installspecial [\dostoprotation]  [or] [0]
+
+%D \macros
+%D   {dostartscaling,
+%D    dostopscaling}
+%D   {}
+%D
+%D Scaling is also supported:
+%D
+%D \starttypen
+%D \dostartscaling {x} {y} ... \dostopscaling
+%D \stoptypen
+%D
+%D Like the previous one, these specials are of category 
+%D \type{or}.
+
+\installspecial [\dostartscaling] [or] [2]
+\installspecial [\dostopscaling]  [or] [0]
+
+%D \macros
+%D   {dostartmirroring,
+%D    dostopmirroring}
+%D   {}
+%D
+%D And indeed, mirroring is there too:
+%D
+%D \starttypen
+%D \dostartmirroring {x} {y} ... \dostopmirroring
+%D \stoptypen
+%D
+%D Again these specials are installed as category \type{or}.
+
+\installspecial [\dostartmirroring] [or] [0]
+\installspecial [\dostopmirroring]  [or] [0]
+
+%D \macros
+%D   {dostartnegative,
+%D    dostopnegative}
+%D   {}
+%D
+%D When producing output for an image setter, negating the 
+%D page comes into view. Here are the tools:
+
+\installspecial [\dostartnegative] [or] [0]
+\installspecial [\dostopnegative]  [or] [0]
+
+%D \macros
+%D   {doselectfirstpaperbin,
+%D    doselectsecondpaperbin}
+%D   {}
+%D
+%D Here are some very printer||specific ones. No further
+%D comment.
+
+\installspecial [\doselectfirstpaperbin]  [or]  [0]
+\installspecial [\doselectsecondpaperbin] [or]  [0]
+
+%D \macros
+%D   {doovalbox}
+%D   {}
+%D
+%D When we look at the implementation, this is a complicated
+%D one. There are seven arguments.
+%D
+%D \starttypen
+%D \doovalbox {w} {h} {d} {linewidth} {radius} {stroke} {fill}
+%D \stoptypen
+%D
+%D This command has to return a \type{\vbox} which can be used
+%D to lay over another one (with text). The radius is in
+%D degrees, the stroke and fill are~\type{1} (true) of~\type{0}
+%D (false). 
+
+\installspecial [\doovalbox] [or] [7]
+
+%D \macros
+%D   {dosetupidentity}
+%D   {}
+%D
+%D We can declare some characteristics of the document with
+%D
+%D \starttypen 
+%D \dosetupidentity {title} {subject} {author} {creator} {date} 
+%D \stoptypen
+%D
+%D All data is in string format. 
+
+\installspecial [\dosetupidentity] [and] [5]
+
+%D \macros
+%D   {dosetuppaper}
+%D   {}
+%D
+%D This special can be used to tell the driver what page size
+%D to use. The special takes three arguments. 
+%D
+%D \starttypen
+%D \dosetuppaper {type} {width} {height}
+%D \stoptypen
+%D
+%D The type is one of the common identifiers, like A4, A5 or 
+%D B2. 
+
+\installspecial [\dosetuppaper] [and] [3]
+
+%D \macros
+%D   {dosetupprinter}
+%D   {}
+%D
+%D Some drivers enable the user to specify the paper type 
+%D used and/or page dimensions to be taken into account. 
+%D
+%D \starttypen
+%D \dosetupprinter {type} {hoffset} {voffset} {width} {height}
+%D \stoptypen
+%D
+%D The first argument is one of \type{letter}, \type{legal}, 
+%D \type{A4}, \type{A5} etc. The dimensions are in 
+%D basepoints. 
+
+\installspecial [\dosetupprinter] [and] [5]
+
+%D \macros
+%D   {% dosetuppage,
+%D    dosetupopenaction, dosetupclosaction,
+%D    dosetupinteraction,
+%D    dosetupscreen,
+%D    dosetupviewmode}
+%D   {}
+%D
+%D Here come some obscure interactive commands. Probably the
+%D specs will change with the development of the macros that
+%D use them.
+%D
+%D The first ones can be used to set up the interaction.
+%D
+%D \starttypen
+%D \dosetupinteraction
+%D \stoptypen
+%D
+%D Normally this command does nothing but giving a message
+%D that some scheme is supported. 
+%D
+%D \starttypen
+%D \dosetupstartaction
+%D \dosetupstopaction
+%D \stoptypen
+%D
+%D These two setup the actions to be executed when the document
+%D is opened and closed. 
+%D
+%D The next command sets up the screen. It takes five 
+%D arguments:
+%D
+%D \starttypen
+%D \dosetupscreen {hoffset} {voffset} {width} {height} {options}
+%D \stoptypen
+%D
+%D The first four arguments are in scaled points. Option~1 
+%D results in a full screen launch.
+%D
+%D \starttypen
+%D \dosetuppageview {keyword}
+%D \stoptypen
+%D
+%D For the moment we only support \type{fit}. 
+
+\installspecial [\dosetupinteraction] [and] [0]
+\installspecial [\dosetupopenaction]  [and] [0]
+\installspecial [\dosetupcloseaction] [and] [0]
+\installspecial [\dosetupscreen]      [and] [5]
+\installspecial [\dosetuppageview]    [and] [1]
+
+%D \macros
+%D   {dostarthide,
+%D    dostophide}
+%D   {}
+%D
+%D Not every part of the screen is suitable for paper. Menus
+%D for instance have no meaning on an non||interactive medium.
+%D These elements are hidden by means of:
+%D
+%D \starttypen
+%D \dostarthide
+%D \dostophide
+%D \stoptypen
+
+\installspecial [\dostarthide]        [or]  [0]
+\installspecial [\dostophide]         [or]  [0]
+
+%D \macros
+%D   {dostartgotolocation, dostopgotolocation,
+%D    dostartgotorealpage, dostopgotorealpage}
+%D   {}
+%D
+%D The interactive real work is done by the following four
+%D specials. The reason for providing the first one with both
+%D a label and a number, is a result of the quite poor
+%D implementation of \type{pdfmarks} in version 1.0 of
+%D Acrobat. Because only pagenumbers were supported as
+%D destination, we had to provide both labels (\DVIWINDO) and
+%D pagenumbers (\PDF). Some drivers use start stop pairs. 
+%D
+%D \starttypen
+%D \dostartgotolocation {w} {h} {url} {file} {label} {page}
+%D \dostartgotorealpage {w} {h} {url} {file}         {page}
+%D \stoptypen
+%D
+%D Their counterparts are:
+%D
+%D \starttypen
+%D \dostopgotolocation  
+%D \dostopgotorealpage  
+%D \stoptypen
+%D
+%D The internal alternative is used for system||generated
+%D links, the external one for user||generated links. The 
+%D Uniform Resource Locator can be used to let the reader 
+%D surf the net. 
+
+\installspecial [\dostartgotolocation] [and] [6]
+\installspecial [\dostopgotolocation]  [and] [0]
+\installspecial [\dostartgotorealpage] [and] [5]
+\installspecial [\dostopgotorealpage]  [and] [0]
+
+%D \macros
+%D  {dostartgotoJS, doflushJSpreamble}
+%D   
+%D
+%D Rather special is the option to include and execute 
+%D JavaScript code. This is a typical \PDF\ option.
+%D
+%D \starttypen
+%D \dostartgotoJS {w} {h} {script}
+%D \stoptypen
+%D
+%D This not so standard \TEX\ feature should be used with 
+%D care. Preamble scripts are flushed by
+%D
+%D \doflushJSpreamble {script}
+
+\installspecial [\dostartgotoJS]    [and] [3]
+\installspecial [\dostopgotoJS]     [and] [0]
+\installspecial [\doflushJSpreamble][and] [1]
+
+%D \macros
+%D   {dostartthisislocation, dostopthisislocation,
+%D    dostartthisisrealpage, dostopthisisrealpage}
+%D   {}
+%D
+%D The opposite commands of \type{\dogotosomething} have only
+%D one argument:
+%D
+%D \starttypen
+%D \dostartthisislocation {label}
+%D \dostartthisisrealpage {page}
+%D \stoptypen
+%D
+%D These commands are accompanied by: 
+%D
+%D \starttypen
+%D \dostopthisislocation  
+%D \dostopthisisrealpage 
+%D \stoptypen
+%D
+%D As with all interactive commands's they are installed as
+%D \type{and} category specials.
+
+\installspecial [\dostartthisislocation] [and] [1]
+\installspecial [\dostopthisislocation]  [and] [0]
+\installspecial [\dostartthisisrealpage] [and] [1]
+\installspecial [\dostopthisisrealpage]  [and] [0]
+
+%D \macro
+%D   {doresetgotowhereever}
+%D 
+%D These and others need:
+
+\installspecial [\doresetgotowhereever] [and] [0]
+
+%D \macros
+%D   {dostartexecutecommand, dostopexecutecommand}
+%D
+%D The actual behavior of the next pair of commands depends 
+%D much on the viewing engine. Therefore one cannot depend 
+%D too much on their support. 
+%D
+%D \starttypen
+%D \dostartexecutecommand {w} {h} {command} {options} 
+%D \stoptypen
+%D
+%D At least the next commands are supported (more examples 
+%D can be found in \type {spec-fdf.tex}: 
+%D
+%D \startregelcorrectie\steluitlijnenin[midden]\leavevmode
+%D \starttabel[|l|l|] 
+%D \HL
+%D \NC \bf command  \NC \bf action                  \NC\SR 
+%D \HL
+%D \NC first        \NC go to the first page        \NC\FR
+%D \NC previous     \NC go to the previous page     \NC\MR
+%D \NC next         \NC go to the next page         \NC\MR
+%D \NC last         \NC go to the last page         \NC\MR
+%D \NC backward     \NC go back to the  link list   \NC\MR
+%D \NC forward      \NC go forward in the link list \NC\MR
+%D \NC print        \NC enter print mode            \NC\MR
+%D \NC exit         \NC exit viewer                 \NC\MR
+%D \NC close        \NC close document              \NC\MR
+%D \NC enter        \NC enter viewer                \NC\MR
+%D \NC help         \NC show help on the viewer     \NC\LR
+%D \HL
+%D \stoptabel
+%D \stopregelcorrectie
+%D
+%D Options are to be passed as a comma separated list of 
+%D assignments.
+
+\installspecial [\dostartexecutecommand] [and] [4]
+\installspecial [\dostopexecutecommand]  [and] [0]
+
+%D \macros
+%D   {dostartobject, 
+%D    dostopobject,
+%D    doinsertobject}
+%D
+%D Reuse of object can reduce the output filesize 
+%D considerably. Reusable objects are implemented with: 
+%D
+%D \starttypen
+%D \dostartobject{class}{name}{width}{height}{depth}
+%D some typeset material
+%D \dostopobject
+%D \stoptypen
+%D
+%D \starttypen
+%D \doinsertobject{class}{name}
+%D \stoptypen
+%D
+%D The savings can be huge in interactive texts. 
+
+\installspecial [\dostartobject]  [or] [5]
+\installspecial [\dostopobject]   [or] [0]
+\installspecial [\doinsertobject] [or] [2]
+
+% %D \macros
+% %D   {dogetobjectreference} 
+% %D
+% %D For very special purposes, one can ask for the internal 
+% %D reference to the object. Beware!
+% 
+% \installspecial [\dogetobjectreference] [or] [3]
+% 
+% %D The first argument is the name, the second a macro that 
+% %D gets the assiciated value.
+
+%D \macros
+%D   {dostartrunprogram, dostoprunprogram,
+%D    dostartgotoprofile, dostopgotoprofile,
+%D    dobeginofprofile,
+%D    doendofprofile}
+%D   {}
+%D
+%D These specials are still experimental. They are not yet
+%D supported by the programs the way they should be.
+%D
+%D {\em --- still undocumented ---}
+
+\installspecial [\dostartrunprogram]  [and] [3]
+\installspecial [\dostoprunprogram]   [and] [0]
+\installspecial [\dostartgotoprofile] [and] [3]
+\installspecial [\dostopgotoprofile]  [and] [0]
+\installspecial [\dobeginofprofile]   [and] [4]
+\installspecial [\doendofprofile]     [and] [0]
+
+%D \macros
+%D   {doinsertbookmark}
+%D 
+%D Bookmarks, that is viewer generated tables of contents, are
+%D a strange phenomena, mainly because \TEX\ can provide
+%D whatever kind of table in much better quality. 
+
+\installspecial [\doinsertbookmark] [and] [5]
+
+%D This special is called as:
+%D 
+%D \starttypen
+%D \doinstallbookmark {level} {nofsubentries} {text} {page} {open}
+%D \stoptypen
+%D
+%D This definition is very \PDF\ oriented, so for more 
+%D information we kindly refer to the \PDF\ manuals. 
+
+%D \macros
+%D   {dosetpagetransition}
+%D
+%D In presentations, fancy page transitions can, at least for a
+%D short moment, let the audience focus at the screen. Like the
+%D previous one, this special is very \PDF. 
+%D
+%D \starttypen
+%D \dosetpagetransition{dissolve}
+%D \stoptypen
+%D
+%D Transitions have symbolic names, like dissolve, box, split,
+%D blinds, wipe and glitter.
+
+\installspecial [\dosetpagetransition] [or] [1]
+
+%D \macros
+%D   {dopresettextfield,dopresetlinefield,
+%D    dopresetchoicefield,dopresetpopupfield,dopresetcombofield,
+%D    dopresetbuttonfield,dopresetcheckfield,
+%D    dopresetradiofield,dopresetradiorecord}
+%D
+%D The special drivers are programmed independant from their
+%D calling macros are thereby use the standard \TEX\ way of
+%D passing parameters. Unfortunately fields often have more
+%D than nine characteristics, so we pack some arguments in one. 
+%D 
+%D \starttypen
+%D \dopresettextfield / \dopresetlinefield
+%D   {name} {width} {height} {default} {length} 
+%D   {style,color} {options} {alignment} {actions}
+%D 
+%D \dopresetchoicefield / \dopresetpopupfield / \dopresetcombofield
+%D   {name} {width} {height} {default} 
+%D   {style,color} {options} {values} {actions}
+%D 
+%D \dopresetpushfield 
+%D   {name} {width} {height} {default}
+%D   {options} {values} {actions}
+%D 
+%D \dopresetcheckfield 
+%D   {name} {width} {height} {default} 
+%D   {options} {values} {actions}
+%D 
+%D \dopresetradiofield
+%D   {name} {width} {height} 
+%D   {options} {parent} {values} {actions}
+%D 
+%D \dopresetradiorecord
+%D   {name} {top} {options} {kids} {actions}
+%D \stoptypen
+
+\installspecial [\dopresetlinefield]   [or] [9]
+\installspecial [\dopresettextfield]   [or] [9]
+\installspecial [\dopresetchoicefield] [or] [8]
+\installspecial [\dopresetpopupfield]  [or] [8]
+\installspecial [\dopresetcombofield]  [or] [8]
+\installspecial [\dopresetpushfield]   [or] [7]
+\installspecial [\dopresetcheckfield]  [or] [7]
+\installspecial [\dopresetradiofield]  [or] [7]
+\installspecial [\dopresetradiorecord] [or] [5]
+
+%D \macros
+%D   {dodefinefieldset,dogetfieldset,doiffieldset}
+%D 
+%D Field sets, used in resetting and submitting, are handled
+%D by:
+
+\installspecial [\dodefinefieldset] [or] [2]
+\installspecial [\dogetfieldset]    [or] [1]
+\installspecial [\doiffieldset]     [or] [1]
+
+%D \macros 
+%D   {dosetfieldstatus}
+%D
+%D For practical reasons we set some field characteristics 
+%D using: 
+%D
+%D \starttypen
+%D \dosetfieldstatus {mode} {parent} {kids} {root}
+%D \stoptypen
+
+\installspecial [\dosetfieldstatus] [or] [4]
+
+%D with:
+
+\def\fieldlonermode {0} % no \chardef here
+\def\fieldparentmode{1} % no \chardef here
+\def\fieldchildmode {2} % no \chardef here
+\def\fieldcopymode  {3} % no \chardef here
+
+%D \macros 
+%D   {doinsertcomment}
+%D
+%D Not so much out ot need, but to be complete, we also 
+%D implement text annotations, so called  comment:
+%D 
+%D \starttypen
+%D \doinsertcomment
+%D   {title} {width} {height} {color} {open} {data} 
+%D \stoptypen
+
+\installspecial[\doinsertcomment] [and] [6]
+
+%D So far for the installation. For quite some time the 
+%D \CONTEXT\ way of specifying the output format has been: 
+%D
+%D \starttypen
+%D \usespecials[ps,yy,win,pdf]
+%D \stoptypen
+%D
+%D Because at \PRAGMA\ we use \DVIPSONE, this was a suitable 
+%D setting, but with \CONTEXT\ going public, the next sequence 
+%D is more suitable for \DVIPS\ users: 
+%D 
+%D \starttypen
+%D \usespecials[reset,ps,tr,pdf]
+%D \stoptypen
+%D
+%D On the other hand, for \PDFTEX\ we needed: 
+%D
+%D \starttypen
+%D \usespecials[tpd]
+%D \stoptypen
+%D
+%D To simplify things, I decided to provide a higher level 
+%D command. 
+%D
+%D \starttypen
+%D \defineoutput[name][specials]
+%D \setupoutput[name,...]
+%D \stoptypen
+%D
+%D In a few lines, we will see some examples. 
+
+\def\defineoutput%
+  {\dodoubleargument\dodefineoutput}
+
+\def\dodefineoutput[#1][#2]%
+  {\setvalue{\??ui#1}{#2}} 
+
+\def\dosetupoutput#1%
+  {\doifdefinedelse{\??ui#1}
+     {\processcommacommand[\getvalue{\??ui#1}]\dousespecials}
+     {\doifdefinedelse{\@@specfil@@#1}
+        {\dousespecials{#1}}
+        {\showmessage{\m!specials}{7}{#1}}}}
+
+\def\setupoutput[#1]%
+  {\resetspecials\processcommacommand[#1]\dosetupoutput}
+
+%D Some suitable definitions are: 
+
+\defineoutput [dvipsone] [dvi,ps,yy]
+\defineoutput [dviwindo] [dvi,ps,yy,win]
+\defineoutput [dvips]    [dvi,ps,tr]
+\defineoutput [dviview]  [dvi,ps,tr,dv]
+\defineoutput [pdftex]   [tpd]   
+\defineoutput [pdf]      [tpd]   
+\defineoutput [acrobat]  [pdf,ps,tr] % use: [acrobat,dvipsone]   
+
+%D Please let me know if we need more. From now on we default
+%D to:
+
+\setupoutput [dvips]
+
+%D We don't enable \ACROBAT, because pure \POSTSCRIPT\ is not
+%D that strong on objects and \PDFTEX\ does a better job. 
+%D Some reasonable alternatives are:
+%D 
+%D \starttypen
+%D \setupoutput [dvipsone,acrobat]
+%D \setupoutput [dviwindo,acrobat]
+%D \stoptypen
+%D 
+%D Although, better is:
+%D 
+%D \starttypen
+%D \setupoutput [pdftex]
+%D \stoptypen
+
+\protect
+
+\endinput