TweetFollow Us on Twitter

Winter 91 - PRINT HINTS WITH LUKE & ZZ

PRINT HINTS WITH LUKE & ZZ

ZZ speaks

Once upon a time, in an engineering department far, far away, the great implementors (GIs) ran across a problem with their Frankensteinian monster. They had designed and built a powerful beast. A beast that had traveled great distances into unknown territories, and that had cut many new paths in the hot lead jungle. Many spoke of the creation, and it had become well known and respected in many lands and platforms. But the complexity that only the great implementors had dared to conceive was being challenged by the great hackers of the land. Many of them had conquered the secrets of the beast, and shared the knowledge of the great implementors. Soon, even mortal hackers would be able to control the beast. This would not do. . .

The GIs traveled far to find the infamous "field workers." They had already given the GIs the gift of dynamic, incomprehensible data structures, and the GIs were hopeful that they could provide something more. They could not. . .

At last, on their return from the field, they ran across a court jester. Like all good jesters, he was trying hard to find some fun. He tried to get the GIs to play a game with him. He tried Monopoly, Pictionary, even checkers, but the GIs were not interested (he did notice a little glimmer when he mentioned thermonuclear war, but not enough to be important). As a last resort, he finally said, "Pick a number." Suddenly, the great gods of arbitration came down on the GIs like a 5-ton weight. "Pick a number!" one of them shouted. "It's beautiful!" laughed another one. And soon they were off to the lab to implement their new discovery.

This folks, is the not-based-on-a-true-story story of the constant named iPfMaxPgs. This constant is part of the Printing Manager, and limits the number of pages that can be spooled (that is, written to disk) in one print job. In the old days, when even engineers at Apple were using floppy drives, the Print Shop came to the conclusion that there should be a limit on the number of pages you could print in a single job. If not, the user could easily use up all the disk space on the boot disk, which at the time, led to other, even more interesting problems. The decision to limit the number of pages was quickly followed by a decision to use the court jester's advice and "pick a number." The magic number is 128, and is referenced by the constant iPfMaxPgs.

So now, you are printing your favorite report, all 130 pages of it, and just to annoy your neighbors, you're printing to your ImageWriter II in Best mode. You've placed the printer next to the window in the bathroom where the acoustics are especially outgoing, and the window is open for the extra cooling effect (at least, that's what you told the neighbors). As the head rips across the bottom of page 128 like nails across the chalkboard, you are suddenly greeted with a Printing Manager error code. Sure, your neighbors are happy, but you still have two pages to go. You frantically dig for that suicide prevention number (that your neighbors have obviously borrowed), but decide instead that printing more than 128 pages in one job would be a great way to get new neighbors.

To print jobs longer than 128 pages, you simply treat them like multiple jobs, printing each set of 128 pages just like the first set. To make this even simpler, it would be nice if there was one line of code that told you when to close the current document and open the new one. Welcome to the MOD squad (or the % Club for you C dudes).

The MOD instruction is very useful for tracking sets of things, like the number of pages in a print job. Most people that have implemented a Macintosh printing loop (you can spot them by the gray hair and growing forehead) use some kind of page loop.

The following code fragments will show the flow of control using the MOD operator. The parameters of the Toolbox routines have been omitted for simplicity.

Before you knew enough words to type 128-page documents, you used to have a print loop that figured out how many pages you had to print and then printed them one at a time.

This works well for bothering neighbors, but you'll never get any For Sale signs with this technique. To print jobs larger than 128 pages, you need to call PrOpenDoc/PrCloseDocwithin the FOR loop. Whenever you reach 128 pages, you need to call PrCloseDoc to close the current document, and then PrPicFile to despool the (now full) spool file. Once this is done, a new document is opened, and everything continues as before.

FOR pageIndex := firstPage TO kNumberOfPages - 1 DO
BEGIN
    (* If we are on page number 128, 
       we need to close and reopen the document *)
    IF (pageIndex - firstPage) MOD iPFMaxPgs = 0 THEN
    BEGIN
        (* Make sure there is a document open before
           calling PrCloseDoc! i.e. if this is the first
           page, don't call PrCloseDoc... *)
        IF pageIndex <> firstPage THEN 
        BEGIN
            PrCloseDoc(...);
            PrPicFile(...);
        END;
        (* Now open a fresh, 128 page spool file. *)
        PrOpenDoc(...);
    END;
    (* Call PrOpenPage/PrClosePage for each page of the document. *)
    PrOpenPage(...);
    PrintAPage(...);
    PrClosePage(...);
END;
(* Finally, close the document and despool the spool file.*)
PrCloseDoc(...);
PrPicFile(...);
.
.
.

Pretty straightforward, but you'd be surprised how many developers the great implementors have caught with this one. Using the above method, you can safely print large documents on any device, without having to worry about overflowing the spool file. As for your neighbors, you could always put a Pause/Continue button in your Printing Status dialog, but then, where's the fun in that?

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

How to get all the crabs in Mr Crab 2
Mr. Crab 2 may look like a cutesy platformer for kids, but if you're the kind of person who likes to complete a game 100%, you'll soon realise that it's a tougher than a crustacean's shell. [Read more] | Read more »
How to be a star in Britney Spears: Amer...
If you've ever wanted to be a star, baby, then you've probably already checked out Britney Spears: American Dream and are happily making your way up the charts. But fame doesn't come easy, and everyone needs a helping hand sometimes. So we've got... | Read more »
AppSpy is hiring a part time Staff Write...
| Read more »
How to save lives in ER Surgery Simulato...
A serious earthquake has struck a nearby town in ER Surgery Simulator - Emergency Doctor, and it’s up to you to save the victims. [Read more] | Read more »
Tips and tricks to get a high score in G...
Ketchapp Games loves the endless runner genre. And its newest game, Gravity Switch, is no exception. Gravity Switch takes a fresh approach, though, as you move a block, suspended in zero gravity, safely through a maze of shifting pillars. If the... | Read more »
Tips and tricks to get a high score in S...
Smash Fu is a high-paced tile-tapping game that requires quick reflexes and some practice. You’ll have to smash bricks with the skill of a seasoned black belt to get a high score. To raise the stakes a bit, you’ll also have to avoid tapping any... | Read more »
How to keep the ball rolling in Dropple
If you're new to the minimalist puzzler Dropple, you may find yourself struggling to make it beyond the first couple of steps before your ball falls into the endless abyss below. [Read more] | Read more »
Game Craft releases new Legend of War ti...
Set for release at the end of this month, real time strategy title Legend of War seems sure to delight with a veritable feast of sweet features to get stuck into. Developed by Game Craft, the game is due for release through both the App Store and... | Read more »
How not to die in Traffic Rider
Traffic Rider, an Out Run-esque game in which your ride a motorcycle recklessly into trffic, might not seem particularly complicated. [Read more] | Read more »
How to adjust your chess game for Regici...
At first glance you might likenWarhammer 40,000: Regicide to Chess - and you'd be right. Regicideputs its own spin on the classic board game though, so some of your tried and true methods may not work quite so well here. [Read more] | Read more »

Price Scanner via MacPrices.net

Textkraft Professional Becomes A Mobile Produ...
The new update 4.1 of Textkraft Professional for the iPad comes with many new and updated features that will be particularly of interest to self-publishers of e-books. Highlights include import and... Read more
SnipNotes 2.0 – Intelligent note-taking for i...
Indie software developer Felix Lisczyk has announced the release and immediate availability of SnipNotes 2.0, the next major version of his productivity app for iOS devices and Apple Watch.... Read more
Pitch Clock – The Entrepreneur’s Wingman Laun...
Grand Rapids, Michigan based Skunk Tank has announced the release and immediate availability of Pitch Clock – The Entrepreneur’s Wingman 1.1, the company’s new business app available exclusively on... Read more
13-inch 2.9GHz Retina MacBook Pro on sale for...
B&H Photo has the 13″ 2.9GHz Retina MacBook Pro (model #MF841LL/A) on sale for $1599 including free shipping plus NY tax only. Their price is $200 off MSRP. Amazon also has the 13″ 3.9GHz Retina... Read more
Apple price trackers, updated continuously
Scan our Apple Price Trackers for the latest information on sales, bundles, and availability on systems from Apple’s authorized internet/catalog resellers. We update the trackers continuously: - 15″... Read more
Clearance 12-inch Retina MacBooks available s...
B&H Photo has dropped prices on leftover 2015 12″ Retina MacBooks with models now available starting at $999. Shipping is free, and B&H charges NY tax only: - 12″ 1.1GHz Gray Retina MacBook... Read more
Check Apple prices on any device with the iTr...
MacPrices is proud to offer readers a free iOS app (iPhones, iPads, & iPod touch) and Android app (Google Play and Amazon App Store) called iTracx, which allows you to glance at today’s lowest... Read more
New 2016 13-inch 256GB MacBook Air on sale fo...
B&H Photo has the new 13″ 1.6GHz/256GB MacBook Air (model MMGG2LL/A) on sale for $1149 including free shipping plus NY sales tax only. Their price is $50 off MSRP. Amazon has the 13″ 1.6GHz/256GB... Read more
Apple refurbished iPad Air 2s available start...
Apple has Certified Refurbished iPad Air 2 available starting at $339. Apple’s one-year warranty is included with each model, and shipping is free: - 128GB Wi-Fi iPad Air 2: $499 - 64GB Wi-Fi iPad... Read more
Accenture and Vatican Opera Romana Pellegrina...
Accenture has announced that the official mobile application for the Extraordinary Jubilee Year of Mercy declared by Pope Francis has been built and launched by Accenture Mobility, part of Accenture... Read more

Jobs Board

*Apple* Nissan Service Technicians - Apple A...
Apple Automotive is one of the fastest growing dealer...and it shows. Consider making the switch to the Apple Automotive Group today! At Apple Automotive , Read more
ISCS *Apple* ID Site Support Engineer - APP...
…position, we are looking for an individual who has experience supporting customers with Apple ID issues and enjoys this area of support. This person should be Read more
Automotive Sales Consultant - Apple Ford Linc...
…you. The best candidates are smart, technologically savvy and are customer focused. Apple Ford Lincoln Apple Valley is different, because: $30,000 annual salary Read more
*Apple* Support Technician II - Worldventure...
…global, fast growing member based travel company, is currently sourcing for an Apple Support Technician II to be based in our Plano headquarters. WorldVentures is Read more
Restaurant Manager (Neighborhood Captain) - A...
…in every aspect of daily operation. WHY YOU'LL LIKE IT: You'll be the Big Apple . You'll solve problems. You'll get to show your ability to handle the stress and Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.