TweetFollow Us on Twitter

LaserWriter PAPA Resource

Volume Number: 13 (1997)
Issue Number: 12
Column Tag: develop

LaserWriter 8.5.1: The Extended 'PAPA' Resource

by Richard Blanchard, RBI Software Systems Inc., Ingrid Kelly, Apple Computer Inc. and Chorng-Shyan Lin, RBI Software Systems Inc.

Overview

Starting with LaserWriter 8.5.1, in order to support different types of desktop printers, the 'PAPA' -8192 resource has been extended from 103 to 1024 bytes long. This TechNote discusses the additional bytes and in what way the LaserWriter 8.5.1 driver uses them.

Note: If your code relies on the size of the 'PAPA' resource, it may crash with LaserWriter 8.5.1 unless you update it to support the extended 'PAPA' resource.

The 'PAPA' Resource

The new 'PAPA' looks just like an old style 'PAPA' at the front of the resource; that is, the 'PAPA' resource begins with three packed Pascal strings representing the printer name, the network type (usually LaserWriter), and the printer's zone. After these strings comes the 4-byte network address.

The new extended 'PAPA' then adds desktop printer (DTP) data beginning at the 104th byte in the resource. The data from bytes 104 to 1024 (1-based indices) is a series of tagged blocks where each block contains a 4-byte tag, followed by a 2-byte length value, and then the actual data. A series of these tagged blocks can reside in bytes 104 to 1024.

Tag Requirements

There are a few requirements for the tagged blocks that go into the extended 'PAPA.' They are:

  • The only required block in an extended 'PAPA' is the 'TAGS' tag which gives the number of valid tag blocks in the extended resource. The 'TAGS' block must be the first tag in the extended record and serves as a validity check.
  • When the extended portion of the 'PAPA' contains multiple tag blocks, each block is required to start on a word (16-bit) boundary. Thus, if a tag block has an odd length, there should be a byte of padding before the start of the next tag block.
  • In order to limit the number of clients that need to understand the extended 'PAPA' format, and to make it easier to change the format in the future, the SettingsLib provides routines for creating and accessing the extended 'PAPA.' Relying on the extended 'PAPA' format rather than using SettingsLib is a bad idea. For more information on SettingsLib, please see Apple's TechNote web site.

Tag Types

Tag: 'TAGS'

Value Size: sizeof(UInt16), 2 bytes

The value of the 'TAGS' block provides the number of valid tag blocks in the extended print record including itself. The 'TAGS' block must be the first tag in the extended print record; a valid extended print record must therefore begin with the byte sequence: 0x5441 0x4753 0x0002.

Tag: 'TYPE'

Value Size: sizeof(OSType), 4 bytes

This tag is optional as its contents are redundant given the PAPA zone name string. If this tag does exists, then its value must match, not literally but in meaning, the DTP type implied by the zone string. Here are the zone string mappings to 'TYPE' values:

Zone Name             'Type'        Definition
String              tag value

=Hld                  'Hold'      Creates and holds spool files. The 
                                  spool files are never processed and the	
                                  DTP is not connected to a real printer.
=Fil*                 '=Fil'      Creates PostScript or EPS files, is 
                                  not connected to a real printer.
=Cst*                 '=Cst'      Creates a PostScript file and then launches
                                  an application to post-process the file.
=LPR*                 '=LPR'      Sends a PostScript job using the    
                                  LPR protocol.
=Ird*                 '=Ird'      Sends a PostScript job over an irda,
                                  infrared, channel.
Valid Zone string      'PAP'      Uses the AppleTalk PAP protocol to print 
                                  the job.

In the preceding mapping, the '*' in the zone name string is a wildcard which can be replaced by zero or more characters of any value. The DTP Utility uses this part of the zone name string to differentiate between DTP printers of the same type with the same name located in different folders.

Beside the tag values 'Hold', '=Fil', '=Cst', '=LPR', '=Ird', and 'PAP ,' other tag values may be added in the future for new DTP types.

Tag: 'TCP '

Value Size: variable size string

If the DTP printer type requires a TCP/IP network address, it is placed in the extended PAPA using the 'TCP ' tag. The value of the tag block is the network address of the printer either as a fully qualified network address, such as colorlaser.apple.com, or in dot format, such as 204.188.109.151.

This tag is required for DTP printers of type '=LPR.' The length of the string is determined from the block length.

Tag: 'Q'

Value Size: variable size string.

If a DTP can use a print queue name, as can LPR DTPs, then the print queue name is placed in a tag value block of type 'Q .' The length of the string is determined from the block length.

Summary of DTP type, zone names, and tags.

DTP Type           PAPA Zone String        Extended Data Tags
PAP                Actual Zone Name        'TYPE' is 'PAP '
Hold                  "     "    "         'TYPE' is 'Hold'
Save to File            =Fil*              'TYPE' is '=Fil'
Custom                  =Cst*              'TYPE' is '=Cst'
LPR	                    =LPR*              'TYPE'is'=LPR'
                                           'TCP'is printer's net address
                                           'Q'is optional and is the name of 
                                           the print spooler.
InfraRed                =Ird               'TYPE'is'=Ird'

Summary

This TechNote has documented the changes in the 'PAPA' resource in LaserWriter 8.5.1. Please beware if your application depends on the size of the 'PAPA' as it may no longer work with LaserWriter 8.5.1.

Further Reference

Acknowledgements

Thanks to Leticia Alarc'n, John Blanchard and Paul Danbold


Richard Blanchard has been programming LaserWriter 8 since its inception and one day hopes to finish it. Working at RBI Software Systems, Inc. Richard, from day to day, codes in C, C++, and Java and tries to draw a bead on the future of network printing.

Ingrid Kelly works in Apple’s Developer Technical Support group. She was sad to see the Blue Angels air show season end this year, but never fear, she is already counting down the days until the start of next year’s air show season. 99...98...97...

Chorng-Shyan Lin is a Macintosh developer at RBI Software Systems, Inc. He can be reached via email at lin@rbi.com.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Latest Forum Discussions

See All

Combo Quest (Games)
Combo Quest 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: Combo Quest is an epic, time tap role-playing adventure. In this unique masterpiece, you are a knight on a heroic quest to retrieve... | Read more »
Hero Emblems (Games)
Hero Emblems 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: ** 25% OFF for a limited time to celebrate the release ** ** Note for iPhone 6 user: If it doesn't run fullscreen on your device... | Read more »
Puzzle Blitz (Games)
Puzzle Blitz 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Puzzle Blitz is a frantic puzzle solving race against the clock! Solve as many puzzles as you can, before time runs out! You have... | Read more »
Sky Patrol (Games)
Sky Patrol 1.0.1 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0.1 (iTunes) Description: 'Strategic Twist On The Classic Shooter Genre' - Indie Game Mag... | Read more »
The Princess Bride - The Official Game...
The Princess Bride - The Official Game 1.1 Device: iOS Universal Category: Games Price: $3.99, Version: 1.1 (iTunes) Description: An epic game based on the beloved classic movie? Inconceivable! Play the world of The Princess Bride... | Read more »
Frozen Synapse (Games)
Frozen Synapse 1.0 Device: iOS iPhone Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Frozen Synapse is a multi-award-winning tactical game. (Full cross-play with desktop and tablet versions) 9/10 Edge 9/10 Eurogamer... | Read more »
Space Marshals (Games)
Space Marshals 1.0.1 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.1 (iTunes) Description: ### IMPORTANT ### Please note that iPhone 4 is not supported. Space Marshals is a Sci-fi Wild West adventure taking place... | Read more »
Battle Slimes (Games)
Battle Slimes 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: BATTLE SLIMES is a fun local multiplayer game. Control speedy & bouncy slime blobs as you compete with friends and family.... | Read more »
Spectrum - 3D Avenue (Games)
Spectrum - 3D Avenue 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: "Spectrum is a pretty cool take on twitchy/reaction-based gameplay with enough complexity and style to stand out from the... | Read more »
Drop Wizard (Games)
Drop Wizard 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Bring back the joy of arcade games! Drop Wizard is an action arcade game where you play as Teo, a wizard on a quest to save his... | Read more »

Price Scanner via MacPrices.net

Our MacBook Price Trackers will show you the...
Our Apple award-winning MacBook Price Trackers are continually updated with the latest information on prices, bundles, and availability for 16″ and 14″ MacBook Pros along with 13″ and 15″ MacBook... Read more
Amazon is offering a 10% discount on Apple’s...
Don’t pay full price! Amazon has 16-inch M4 Pro MacBook Pros (Silver and Black colors) on sale today for 10% off Apple’s MSRP. Shipping is free. These are the lowest prices currently available for 16... Read more
13-inch M4 MacBook Airs on sale for $150 off...
Amazon has new 13″ M4 MacBook Airs on sale for $150 off MSRP right now, starting at $849. Sale prices apply to most colors and configurations. Be sure to select Amazon as the seller, rather than a... Read more
15-inch M4 MacBook Airs on sale for $150 off...
Amazon has new 15″ M4 MacBook Airs on sale for $150 off Apple’s MSRP, starting at $1049. Be sure to select Amazon as the seller, rather than a third-party: – 15″ M4 MacBook Air (16GB/256GB): $1049, $... Read more
Amazon is offering a $50 discount on Apple’s...
Amazon has Apple’s 11th-generation A16 iPads in stock on sale for $50 (or a little more) off MSRP this week. Shipping is free: – 11″ 11th-generation 128GB WiFi iPads: $299 $50 off MSRP – 11″ 11th-... Read more
Clearance 13-inch M1 MacBook Airs available f...
Walmart has clearance, but new, Apple 13″ M1 MacBook Airs (8GB RAM, 256GB SSD) available online for $649, $360 off original MSRP, in Space Gray, Silver, and Gold colors. These are new MacBooks for... Read more
iPad minis on sale for $100 off Apple’s MSRP...
Amazon is offering $100 discounts (up to 20% off) on Apple’s newest 2024 WiFi iPad minis, each with free shipping. These are the lowest prices available for new minis among the Apple retailers we... Read more
AirPods Max headphones on sale for $479, $70...
Amazon has AirPods Max with USB-C on sale for $479.99 in all colors. Shipping is free. Their price is $70 off Apple’s MSRP, and it’s the lowest price available today for AirPods Max. Keep an eye on... Read more
14-inch M4 Pro/M4 Max MacBook Pros on sale th...
Don’t pay full price! Get a new 14″ MacBook Pro with an M4 Pro or M4 Max CPU for up to $320 off Apple’s MSRP this weekend at these retailers…they are the lowest prices available for these MacBook... Read more
Get a 15-inch M4 MacBook Air for $150 off App...
A couple of Apple retailers are offering $150 discounts on new 15″ M4 MacBook Airs this weekend. Prices at these retailers start at $1049: (1): Amazon has new 15″ M4 MacBook Airs on sale for $150 off... Read more

Jobs Board

All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.