TweetFollow Us on Twitter

June 93 - Letters

LETTERS

DEBUGGING LESSON
I just finished reading the debugging article in Issue 13 and I wondered if you had ever written up anything about this one:
TYPE
	LHdl = ^LPtr;
	LPtr = ^LONGINT;

{$S Fill_Seg}
PROCEDURE FillWithData(h:Handle);
BEGIN
h^^ := 23;
END;


{$S Main}

PROCEDURE CanYouSpotTheProblem;

VAR
	h :LHdl;

BEGIN
	h := LHdl(NewHandleClear(Size));
	FillWithData(h);
END.
I call this "Routines That Don't Move Memory, Most of the Time." The problem comes about because of the hidden trap to LoadSeg. If all the code resources are preloaded, everything is OK. But if they aren't, the call to FillWithData may cause a memory move, and h is not locked. This is especially vile and nasty when, like us, you run in a very limited heap and unload your code frequently. I know that if you read Inside Macintosh Volume II very carefully this is clear. But most of the interesting examples are the ones that are well documented but hard to catch.
--Bob Tipton

Thanks for the example. You're right, of course; calling routines in other, unloaded segments can indeed move memory. This is documented in various places, but unless you understand very clearly how your program occupies memory and how the Segment Loader works, it's easy to overlook. Judicious use of a good heap scramble/purge will catch this one before it catches you. Thanks for writing!
--Dave Johnson

WHERE IN THE WORLD(SCRIPT)?
I was looking for the WorldScript folder on Issue 12's Developer CD, "Wayne's GWorld" (Dev.CD Nov/Dec 92). According to the Contents Catalog stack, the WorldScript folder should be found in this path: Dev.CD Nov/Dec 92: System Software: WorldScript. But it's not there. I talked with a friend of mine who has the same CD, and he found the folder where it's supposed to be. We checked our CDs and found out that his says 564.6 MB on disc, 69.7 MB available, while mine says 555.5 MB on disc, 78.9 MB available. What's going on?
--Toru Kawate

P.S. Thank you for the fine journal and CD. I really enjoy them.

I received Issue 12 of develop with the Nov/Dec 1992 Developer CD Series disc. I enjoy the Developer CD but had the following trouble: I used the Contents Catalog on the CD and found the title"WorldScript." But I didn't find the folder at the pathname Dev.CD Nov/Dec 92: System Software: WorldScript.
--Hirokazu Yaguchi

At the last minute, WorldScript was pulled from the CD accompanying develop, but there wasn't enough time to remove it from the Contents Catalog. WorldScript did, however, remain on the Developer CD Series disc received monthly by members of Apple's developer programs. The reason for this is tied in with why develop now has its own CD, separate from the Developer CD Series disc; for details, see the editorial on page 2.
--Caroline Rose

WHEN TO EXPECT DEVELOP
Sorry to disturb you, but because I've had problems with my subscription (two copies, no copies) -- which I've worked out, I think, with the DEV.SUBS people -- I'm wondering: Is there some sort of publication schedule available that will allow me to fret about this without disturbing anyone? ("Gee, it's two weeks past when this should be out . . . what am I missing out on?!")

Y'all are doing a fine job. Just be sure to run your issues through a Quark SmugCheck to keep the content only kinda wacky and smug without being too much that way. Thanks!
--J. C. Burns

I'm sorry you've had subscription problems, but I'm grateful that you pursued them with DEV.SUBS rather than sending an AppleLink to CROSE or DEVELOP; many developers make the mistake of contactingdevelop staff with these problems, but it's really out of our realm. We are, however, doing our best to make the problems go away.

If you're located in the U.S., you should normally receive develop around the first of March, June, September, and December. (If you're outside the U.S., it's hard to say, because develop might need to wait for other materials to be merged into the same mailing.)

Thanks for the tip on SmugCheck; it's just what we need!
--Caroline Rose

M.TN.DESIGNATIONS
I notice you still add the numbers in references to Tech Notes. If dropping the numbers were such progress, that wouldn't be necessary. And the new alphanumeric reference codes are not used.

I'm a technical person who is used to abbreviations everywhere for conciseness. Besides, citing with full titles adds noise and a lot of repetitiveness.
--Peter Fink

We decided to include the old numbers in references to Tech Notes to help out those people who like to use hard copy but still have the numbered versions. We'll stop doing that once enough time has elapsed that we expect everyone will have the new, unnumbered versions.

For a variety of reasons, we decided not to include the new designations, such as "M.PT.StandAloneCode," which identify the category/folder for each Note. We figured people could find the Notes in the new file organization easily enough -- a Note on QuickTime is in the QuickTime folder, right? But we've since realized that the category isn't always obvious. So starting with this issue we refer to Notes by category -- for example, "See the Macintosh (Platforms & Tools) Technical Note, 'Stand-Alone Code, ad nauseam.'"

Many developers simply look up specific notes in the various Tech Note indexes, and don't use the special designations at all. For those who do use them, they've been improved to correlate more closely to the Notes' titles; for more on this and other recent Tech Note improvements, see the box on this page.

We're always open to suggestion, but so far you're the only one to mention this. If others reading this reply have similar feedback, I hope they'll let us know.
--Caroline Rose

TECH NOTES AND Q&AS: STATE OF THE UNION

BY NEIL DAY, TECH NOTE AND SAMPLE CODE POOH-BAH

On the August 1992 Developer CD Series disc, the new organization of Macintosh Technical Notes made its debut. Since then, we've been listening for suggestions for improvement. The vast majority of the feedback has been positive, but you did point out a few areas for attention:

  • Better name correlation: Filenames, titles, and designations like "M.PT.StandAloneCode" needed to be more tightly bound to one another. The latest release fixes this problem; Tech Notes should be easier to find across the print and electronic versions.
  • Organization: Tech Notes are now organized alphabetically by title within each section. This was always the intention, but because filenames and titles didn't really match, things were a little haphazard.
  • Locating items in print: We've added the designation to the footer of each note, so you can quickly tell where you are as you flip through the pages.

Many of you have asked how to quickly locate the most recently written and updated Tech Notes. On the CD, aliases to the latest Notes can always be found in the "What's new on this CD?" folder. Using the Finder's View by Date option on the category folders is a handy way to see the most recent updates.

Also, please note that to group related information more logically, we've integrated Q&As into the Tech Note library. Q&As appear at the beginning of every section in the print version, and have the label "Essential" in the electronic version (or a different label if you've changed that label name on your system).

Many of you noticed that the Tech Note and Q&A stacks have gone away: the Tech Note library is now available in Apple DocViewer format (as well as Microsoft Word files). You should find the searching and viewing in Apple DocViewer much more usable; please check it out.

These changes should make information much easier to find. As always, if you have suggestions or ideas for improving the Tech Note library, please let me know!

Thanks to Doug McKenna, the author of Resorcerer, for pointing out these problems.


WE WORRY WHEN YOU DON'T WRITE We welcome timely letters to the editors, especially from readers reacting to articles that we publish in develop. Letters should be addressed to Caroline Rose (or, if technical develop-related questions, to Dave Johnson) at Apple Computer, Inc., 20525 Mariani Avenue, M/S 75-2B, Cupertino, CA 95014 (AppleLink CROSE or JOHNSON.DK). All letters should include your name and company name as well as your address and phone number. Letters may be excerpted or edited for clarity (or to make them say what we wish they did). *

Send your feedback on Tech Notes or Sample Code to Neil at AppleLink NMDAY or on the Internet at nmday@apple.com.*

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Latest Forum Discussions

See All

How to evolve Eevee in Pokemon GO
By now, almost everyone should be hip to how to evolve Pokemon in Pokemon GO (and if not, there's a guide for that). Just gather enough candy of the appropriate type, feed them all to the Pokemon, and evolution happens. It's a miracle that would... | Read more »
CSR Racing 2: Guide to all game modes
It might not seem like there are all that many ways to go fast in a straight line, but CSR Racing 2 begs to differ. [Read more] | Read more »
Bulb Boy (Games)
Bulb Boy 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Multi-award winning 2D point & click horror adventure about a boy with a glowing head. | Read more »
5 top free emoji keyboard apps
If we're not at peak emoji yet as a society, it feels like we definitely should be. The emoji concept has gone far beyond what anyone in Japan could have envisioned when the people there unleashed it on an unsuspecting world, but the West has... | Read more »
How to unlock more characters in Disney...
One of the big charms of Disney Emoji Blitz is seeing a wide variety of beloved Disney and Pixar characters transformed into smiling emojis. Even someone like the sneaky Randall from Monsters Inc., who probably never cracked a smile on film, is... | Read more »
Cubway (Games)
Cubway 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Cubway is a journey with an abstract story of lifecycle of rebirth, called Samsara. Guide the cube through the long way full of dangers... | Read more »
Colorcube (Games)
Colorcube 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Turn pieces and blend colours in this minimal yet visually stunning puzzler.Over 200 handcrafted and challenging levels. Features... | Read more »
Doodle God Griddlers (Games)
Doodle God Griddlers 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: | Read more »
Crusader Kings: Chronicles (Games)
Crusader Kings: Chronicles 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Crusader Kings: Chronicles is an interactive text based game that puts you in the shoes of Guy de Rose as you make... | Read more »
Roads of Rome: New Generation (Games)
Roads of Rome: New Generation 1.0 Device: iOS Universal Category: Games Price: $5.99, Version: 1.0 (iTunes) Description: | Read more »

Price Scanner via MacPrices.net

Charitybuzz Set to Auction Unique Apple-1 Com...
Offering an opportunity to own the computer that sparked a revolution, on Monday, July 25, leading online charity auction platform Charitybuzz will auction what is claimed to be the world’s most... Read more
MacBook Airs on sale for up to $150 off MSRP
Amazon has 11″ and 13″ MacBook Airs on sale for up to $150 off MSRP for a limited time. Shipping is free: - 13″ 1.6GHz/128GB MacBook Air (sku MMGF2LL/A): $899.99 $100 off MSRP - 13″ 1.6GHz/256GB... Read more
Apple refurbished 13-inch Retina MacBook Pros...
Apple has Certified Refurbished 13″ Retina MacBook Pros available for up to $270 off the cost of new models. An Apple one-year warranty is included with each model, and shipping is free: - 13″ 2.7GHz... Read more
Apple refurbished 11-inch MacBook Airs availa...
Apple has Certified Refurbished 11″ MacBook Airs (the latest models), available for up to $170 off the cost of new models. An Apple one-year warranty is included with each MacBook, and shipping is... Read more
Apple iPad Pro Sales Far Outpacing Microsoft...
A report on Appleinsider notes that despite Microsoft Surface tablet PC sales growing by 9 percent year over year, revenues remained below $1 billion, and are down sequentially from the $1.1 billion... Read more
DEVONthink 2.9 Features Ultra-fast, Robust, A...
DEVONthink 2.9 allows users to keep databases synchronized using many means of transport. It transmits them between Macs on the local network or stores them in a syncable form on removable hard... Read more
12-inch WiFi Apple iPad Pros on sale for up t...
B&H Photo has 12″ WiFi iPad Pros on sale for up to $100 off MSRP, each including free shipping. B&H charges sales tax in NY only: - 12″ Space Gray 32GB WiFi iPad Pro: $749 $50 off MSRP - 12″... Read more
Apple refurbished 15-inch Retina MacBook Pros...
Apple has Certified Refurbished 2015 15″ Retina MacBook Pros available for up to $380 off the cost of new models. An Apple one-year warranty is included with each model, and shipping is free: - 15″ 2... Read more
Apple refurbished Mac minis available for up...
Apple has Certified Refurbished Mac minis available starting at $419. Apple’s one-year warranty is included with each mini, and shipping is free: - 1.4GHz Mac mini: $419 $80 off MSRP - 2.6GHz Mac... Read more
Apple Mac Sales Finally Colliding With ‘Innov...
After successfully swimming against a tide of diminishing PC sales through 2014 and 2015, it appears that Apple has finally stopped defying gravity and is running up against the unwritten “innovate... Read more

Jobs Board

*Apple* Solutions Consultant - APPLE (United...
Job Summary As an Apple Solutions Consultant, you'll be the link between our future customers and our products. You'll showcase your entrepreneurial spirit as you Read more
*Apple* Professional Learning Specialist - A...
Job Summary The Apple Professional Learning Specialist is a full-time position for one year with Apple in the Phoenix, AZ area. This position requires a high Read more
*Apple* Picker - Apple Hill Orchard (United...
Apple Hill Orchard, Co. Rte. 21,Whitehall, NY 9/7/16-10/228/16. Pick fresh market or processing apples Productivity of 60 boxes and 80 boxes processing fruit per Read more
*Apple* Solutions Consultant - APPLE (United...
Job Summary As an Apple Solutions Consultant, you'll be the link between our future customers and our products. You'll showcase your entrepreneurial spirit as you Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.