TweetFollow Us on Twitter

Customizing Desktop Printer Util

Volume Number: 13 (1997)
Issue Number: 11
Column Tag: develop

Customizing Desktop Printer Utility

by Brendan Galten and Ingrid Kelly, Apple Computer, Inc.

In the current LaserWriter 8 driver, the Chooser lists printers which are available on the AppleTalk network (either LocalTalk or AppleTalk) with an NBP type of "LaserWriter." When the user selects one of these printers, LaserWriter 8 creates a desktop printer by sending an Apple Event to the Finder. In the past, this mechanism of setting up printers has served the needs of most users. However, with LaserWriter 8.5.1, Apple is responding to several requests for more flexible desktop printing functionality. To this end, Apple has introduced a new application called Desktop Printer Utility which enables users to create additional types of desktop printers. Users can now create desktop printers which use the Unix lpr protocol for printing, in addition to the regular AppleTalk PAP printers. There are also "hold" printers which represent local print queues and "virtual" printers which represent printers which are not available on the network.

Along with the expanded capabilities, Desktop Printer Utility is also customizable. LaserWriter 8.5.1 and Desktop Printer Utility (together) support the creation and use of desktop printers known as Custom DTPs. When printed to, Custom DTPs cause the LaserWriter 8.5.1 driver to create a PostScript file and to launch an application that can post-process the PostScript. This post-processing application can do anything it likes with the PostScript file, such as converting the PostScript into another file format, transferring the file to another location using a modem or a network connection, or displaying the PostScript file to the user. This article describes how a developer might customize Desktop Printer Utility for use with an application.

Customizing the DTP Utility

In order to add a new custom DTP to the list of supported DTPs in Desktop Printer Utility, you must add resources to the utility's resource fork. Desktop Printer Utility contains templates to ease the creation of these resources.

'CsDs'(CustomDTPResource) Resource

In order to customize Desktop Printer Utility, a 'CsDs' (CustomDTPResource) resource must be added to Desktop Printer Utility. The LaserWriter uses this information to find the appropriate application to launch and to customize your DTP interface.

The resource's format is defined by the structure 'CustomAppDesc:'

#define kVariableLen 1

struct CustomAppDesc{
    OSType appSignature;    
    Str255 docType;    
    Str255 helpText;    
    Str255 usage;      
    Str255 appFileName;     
    short numOfHintsFollow;  
    HintRsrcSpec hintRsrc[kVariableLen];  
};
typedef struct CustomAppDesc CustomAppDesc;
  • appSignature: The application signature of the application to launch. The LaserWriter driver uses this information to find the application on all mounted volumes which are available to the user.
  • docType: A string that describes the type of custom DTP. This string appears in the list of document types when "New" menu is selected. This string is highlighted in Figure 1.
  • helpText: This string appears when your custom DTP is selected. This string will appear in the "New" dialog field just below the DTP choices. This string appears as 'Custom DTP Example Help Text' in Figure 1.
  • usage: A string that describes the usage of your custom DTP. This string appears as 'Custom DTP Example Usage string' in Figure 2.
  • appFileName: The name of the application to launch. The LaserWriter driver uses this information to find the application on disks which are available to the user as well as to provide error messages to the user (e.g. "SurfWriter could not be launched due to insufficient memory").
  • numOfHintsFollow: The number of hints provided in the hintRsrc array. See the 'Hints Resources' section for more details.
  • hintRsrc: An array of hints that outlines the kind of PostScript that should be generated by the driver. See the 'Hints Resources' section for more details.

Figure 1.

Figure 2.

Hints Resources (optional)

The CustomDTPResource can provide 'hints' about the PostScript the driver should generate. Each 'CustomDTPResource' contains the field 'numOfHintsFollow' which represents the number of 'hints' provided. The 'hints' data is placed in an array that contains 'numOfHintsFollow' number of copies of the structure:

  struct HintRsrcSpec{
    OSType rsrcType;    
    short rsrcID
  };
  typedef struct HintRsrcSpec HintRsrcSpec;

Each entry in the array points to a resource which is converted to a hint in the driver's preferences. The hint resource types, which are currently supported, have the following formats:

/* PostScript Level */

The application that postprocesses the PostScript for a custom DTP may require or prefer a certain PostScript level. The 'pslv' hint specifies the desired PostScript level.

Resource type 'PSlv' 
typedef struct{
    OSType hintType;      //'pslv' hint type
    long hintId;        // set to 1
    long psLevel;
}PSlvResource;

#define kHintLanguageLevelTag  'pslv'
#define kHintLanguageLevelId  1

The possible(current) values for psLevel which can be set are:

  -3,  Level 2 and 3 
  -2,  Level 1 and 2 
  -1,  Unknown Level 
   0,  Other Level     //do not use
   1,  Level 1 
   2,  Level 2 
   3   Level 3

Note: -3 will create PostScript that takes advantage of PostScript level 2 and level 3 printers, but the data may fail on a level 1 printer. -2 will create PostScript that will succeed on level 1, 2, and 3 printers.

/* Binary OK - 'bnok' */

This hint allows or disallows the use of binary data in the PostScript file.

Resource type 'BNok' 
typedef struct{
    OSType hintType;    //'bnok' hint type
    long hintId;        // set to 1
    TriState binaryOK;      
}BNokResource;

#define kHintADOIsBinaryOKTag  'bnok'
#define kHintADOIsBinaryOKId  1

There are three acceptable settings for binaryOK which answer the question, "Is binary data ok?":

   0,    False
   1,    True
   2     Unknown     //do not use

Note: This hint should not be created in the DTP with a value of unknown; however, it is available for future use.

/* Job Type - 'jobt' */

This hint specifies the type of PostScript to generate.

Resource type 'JObt' 
typedef struct{
    OSType hintType;    //'jobt' hint type
    long hintId;        // set to 1
    char jobType;      
}JObtResource;

#define kHintJobTypeTag   'jobt'
#define kHintJobTypeId    1

Currently only two PostScript forms for jobType are available:

    0,  psJobPostScript 
    1   psJobEPSNoPreview

/* Font Handling - 'font' */

This hint specifies the font inclusion. The font handling hint consists of a four-byte flag followed by a list of NULL terminated font names.

Resource type 'FOnt'
typedef struct{
    OSType hintType;      //'font' hint type
    long hintId;          //set to 1
    long tag;    
    unsigned char name[1];  
}FOntResource;

#define kHintIncludeFontsTag    'font'
#define kHintIncludeFontsId      1

The possible values for tag are:

    0,  kIncludeNoFontsOtherThan
    1   kIncludeAllFontsBut

If the flag is 'kIncludeNoFontsOtherThan', the utility will only include the font definitions of fonts that are listed after the flag. If there are no font names after the flag, no font resources are included in the output. If the flag is 'kIncludeAllFontsBut', font resources are included in the output unless the font names are listed. To include all fonts, use the 'kIncludeAllFontsBut' flag with no fonts listed afterwards.

Sample Custom DTP

Following is a sample of a custom DTP that excludes Courier and Helvetica from the PostScript file via a 'CsDs' and 'FOnt' resource. This sample is intended to give developers an idea of how easy it is to customize the DTP Utility. The first step towards adding the Custom DTP is to create a hint resource of the correct type. The example shown is the 'FOnt' resource which provides data about font inclusion.

Figure 3.

The second step is to associate the hint with a particular DTP by adding hint resource information to the 'CsDs' resource for a particular DTP.

Figure 4.

And that's all that is required to get the DTP Utility to create a custom DTP that produces a PostScript file without Courier and Helvetica.

Limitations of the DTP Utility

Due to the parallel development schedules of Mac OS 8.0 and LaserWriter 8.5.1, DTP Utility 1.0 (which ships with LaserWriter 8.5.1) will not install on Mac OS 8.0. It will, however, work with Mac OS 8.1, due out in Fall of 1997.

Licensing the DTP Utility

In order to ship a customized DTP Utility with your application, you must license the DTP Utility from Apple. Please contact Apple's Software Licensing group (sw.license@apple.com or 512-919-2645) for more information.

Summary

This article has described and demonstrated all that is necessary for you to customize Desktop Printer Utility. We encourage all developers to give this a try.

Further References

  • 'Introducing the LaserWriter Driver Version 8.5.1' by Ingrid Kelly in this issue of MacTech.

Acknowledgements

Thanks to Leticia Alarcon, John Blanchard, Richard Blanchard, Paul Danbold and David Gelphman.


Brendan Galten is a software engineer with RBI Software Systems in Berkeley, Ca. He resides in Petaluma, Ca. When not writing software, he enjoys spending time with his beautiful wife, Rosemary, and making sure his 9 month old daughter, Kelly, doesn't eat bugs. Camping, fishing and woodworking occupy what little time is left.

Ingrid Kelly is a technical support engineer at Apple Computer. She and her husband, Lance, are constantly in search of the best new restaurants in the San Francisco Bay Area. One day, they may decide to leave the computer industry altogether and open one of these great restaurants themselves. For now, though, they are content helping Silicon Valley grow.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Little Snitch 3.5.3 - Alerts you about o...
Little Snitch gives you control over your private outgoing data. Track background activity As soon as your computer connects to the Internet, applications often have permission to send any... Read more
Cocktail 8.4 - General maintenance and o...
Cocktail is a general purpose utility for OS X that lets you clean, repair and optimize your Mac. It is a powerful digital toolset that helps hundreds of thousands of Mac users around the world get... Read more
PDFKey Pro 4.3 - Edit and print password...
PDFKey Pro can unlock PDF documents protected for printing and copying when you've forgotten your password. It can now also protect your PDF files with a password to prevent unauthorized access and/... Read more
Kodi 15.0.beta1 - Powerful media center...
Kodi (was XBMC) is an award-winning free and open-source (GPL) software media player and entertainment hub that can be installed on Linux, OS X, Windows, iOS, and Android, featuring a 10-foot user... Read more
DiskCatalogMaker 6.4.12 - Catalog your d...
DiskCatalogMaker is a simple disk management tool which catalogs disks. Simple, light-weight, and fast. Finder-like intuitive look and feel. Super-fast search algorithm. Can compress catalog data... Read more
Macs Fan Control 1.3.0.0 - Monitor and c...
Macs Fan Control allows you to monitor and control almost any aspect of your computer's fans, with support for controlling fan speed, temperature sensors pane, menu-bar icon, and autostart with... Read more
Lyn 1.5.11 - Lightweight image browser a...
Lyn is a lightweight and fast image browser and viewer designed for photographers, graphic artists and Web designers. Featuring an extremely versatile and aesthetically pleasing interface, it... Read more
NeoOffice 2014.11 - Mac-tailored, OpenOf...
NeoOffice is a complete office suite for OS X. With NeoOffice, users can view, edit, and save OpenOffice documents, PDF files, and most Microsoft Word, Excel, and PowerPoint documents. NeoOffice 3.x... Read more
LaunchBar 6.4 - Powerful file/URL/email...
LaunchBar is an award-winning productivity utility that offers an amazingly intuitive and efficient way to search and access any kind of information stored on your computer or on the Web. It provides... Read more
Remotix 3.1.4 - Access all your computer...
Remotix is a fast and powerful application to easily access multiple Macs (and PCs) from your own Mac. Features Complete Apple Screen Sharing support - including Mac OS X login, clipboard... Read more

Crossy Road Devs Hipster Whale are Bring...
Hipster Whale, the minds behind the rather popular (and rather great) Crossy Road, have teamed-up with Bandai Namco to create PAC-MAN 256: an absolutely bonkers looking maze runner chaser thing. | Read more »
Meet the New Spotify Music
Spotify Music  has a lot going on. They're introducing 3 new modes to serve all your musical needs, with the "Now" start page  gives you curated playlists based on your particular tastes. As you listen the app will learn more about your tastes and... | Read more »
What the Apple Watch Gets Right, and Wha...
| Read more »
Celebrate PAC-MAN's 35th Birthday W...
BANDAI NAMCO Entertainment America is celebrating PAC-MAN's 35th anniversary by releasing updates for PAC-MAN and PAC-MAN Lite for iOS. [Read more] | Read more »
Strike Wing Episode 2 has Landed on the...
Strike Wing: Raptor Rising is an exciting space combat simulator by Crescent Moon Games, which was recently updated to continue the story with Episode 2. [Read more] | Read more »
Kiqplan Expands its Interactive Coaching...
The makers of Fitbug have been hard at work on their Kiqplan lineup, and have added four new summer themed plans to help you get the most out of your workout. [Read more] | Read more »
Make a Photobook in Minutes with Pictyea...
What happens when you can't stop taking photos and have an urge to create a photobook? Pictyear saves the day. [Read more] | Read more »
This Week at 148Apps: May 18-22, 2015
May Days at 148Apps How do you know what apps are worth your time and money? Just look to the review team at 148Apps. We sort through the chaos and find the apps you're looking for. The ones we love become Editor’s Choice, standing out above the... | Read more »
Biz Builder Delux (Games)
Biz Builder Delux 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: Ah, there's nothing like the rhythmic bustle of a burgeoning business burg... especially when you're the one building it... | Read more »
Auroch Digital is Bringing Back Games Wo...
| Read more »

Price Scanner via MacPrices.net

What Would the ideal Apple Productivity Platf...
For the past four years I’ve kept a foot in both the Mac and iPad camps respectively. my daily computing hours divided about 50/50 between the two devices with remarkable consistency. However, there’... Read more
New 13-inch 2.9GHz Retina MacBook Pro on sale...
B&H Photo has the 13″ 2.9GHz/512GB Retina MacBook Pro on sale for $1699.99 including free shipping plus NY tax only. Their price is $100 off MSRP, and it’s the lowest price for this model from... Read more
12-inch MacBook stock status for Monday, May...
The new 12″ Retina MacBooks are still on backorder at The Apple Store with a 3-5 week waiting period. However, a few models are in stock today at Apple resellers. Stock is limited, so act now if you’... Read more
New 27-inch 3.3GHz 5K iMac in stock with free...
Adorama has the new 27″ 3.3GHz 5K iMac in stock today for $1999 including free shipping plus NY & NJ sales tax only. Adorama will include a free copy of Apple’s 3-year AppleCare Protection Plan. Read more
Memorial Day Weekend Sale: New 27-inch 3.3GHz...
Best Buy has the new 27″ 3.3GHz 5K iMac on sale for $1899.99 this weekend. Choose free shipping or free local store pickup (if available). Sale price for online orders only, in-store prices may vary... Read more
OtterBox Maximizes Portability, Productivity...
From the kitchen recipe book to the boarsroom presentation, the OtterBox Agility Tablet System turns tablets into one of the most versatile pieces of handheld technology available. Available now, the... Read more
Launch of New Car App Gallery and Open Develo...
Automatic, a company on a mission to bring the power of the Internet into every car, has announced the launch of the Automatic App Gallery, an app store for nearly every car or truck on the road... Read more
Memorial Day Weekend Sale: 13-inch 1.6GHz Mac...
Best Buy has the new 13″ 1.6GHz/128GB MacBook Air on sale for $849 on their online store this weekend. Choose free shipping or free local store pickup (if available). Sale price for online orders... Read more
Memorial Day Weekend Sale: 27-inch 3.5GHz 5K...
Best Buy has the 27″ 3.5GHz 5K iMac on sale for $2099.99 this weekend. Choose free shipping or free local store pickup (if available). Sale price for online orders only, in-store prices may vary.... Read more
Sale! 16GB iPad mini 3 for $349, save $50
B&H Photo has the 16GB iPad mini 3 WiFi on sale for $349 including free shipping plus NY sales tax only. Their price is $50 off MSRP, and it’s the lowest price available for this model. Read more

Jobs Board

Architect / Senior Software Engineer, *Apple...
Changing the world is all in a day039s work at Apple . If you love innovation, here039s your chance to make a career of it. You039ll work hard. But the job comes with Read more
*Apple* Pay Support Readiness Project Manage...
Changing the world is all in a day039s work at Apple . If you love innovation, here039s your chance to make a career of it. You039ll work hard. But the job comes with Read more
Hardware Design Validation Engineer - *Apple...
**Job Summary** The Apple Watch team is looking for a Hardware Design Validation Engineer. This person will be part of the Apple Watch hardware team with Read more
Sr. Payment Program Manager, *Apple* Pay -...
**Job Summary** Apple Pay is an exciting environment and a…devices in a simple, private and secure way. The Apple Pay Team is looking for an experienced Senior Read more
Project Manager / Business Analyst, WW *Appl...
…a senior project manager / business analyst to work within our Worldwide Apple Fulfillment Operations and the Business Process Re-engineering team. This role will work Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.