LETTERS

NEAT THREADS
I've just finished experimentally adding the Threads Package to my current application. I was amazed at how painlessly it could be added. What I felt was truly remarkable was that I use THINK C's^TM object-oriented extensions (which I refer to as C+-) along with the THINK Class Library, and it took less than 10 minutes to perform all the necessary conversions. Pretty neat.

I'm linking to ask whether you have any information about using the Threads Package with THINK C and TCL, and whether there are any special considerations involved in using threads with or inside methods. Just using them inside a method with a single instance, with no reference to instance variables, is demonstrably effective, but this case is logically indistinguishable from conventional code. I suspect that use with objects might require custom fSwapIn and fCopyContext routines to preserve this, the handle to the object's instance. In THINK C, this is internally kept in an address register.

If the default context-saving routines save A0-A4 register states as well as the stack, this should automatically be preserved. Whether registers are preserved does not seem to be documented in your otherwise nifty develop article. Logic says some must be preserved (A5 at least), but have you been prescient enough to save all of them?
--Kirk Kerekes

Thanks for your truly inspiring link! It really makes a difference for me to get feedback like this. I don't foresee any special problems threading THINK C code. All the data and address registers are saved. The FPU registers are saved only if you specifically request that they be saved at InitThreads time, and then only when you have an FPU. Remember to be careful about segment unloading.

I'm at your service if you need any help with threads. Feel free to contact me by telephone. My number is (408)974-0355.
--Michael Gough

MISSING SNIPPETS
Am I blind? Issue 6 of develop, page 88, talks about code snippets, but I can't find them anywhere. Are they inside a stack somewhere, or did they miss getting on the CD?
--Greg Johnson

You are not blind. Snippets did not make it onto that CD, but they've made it onto the Developer Essentials disc for this issue of develop. They're also available via AppleLink®, in the Developer Technical Support folder on the Developer Services Bulletin Board, as well as in the Dev Tech Answers library.
--Caroline Rose

MISSING TRUETYPE INIT
Recently I received Issue 6 of develop . I enjoy reading the articles and would like to make a comment.

Since Apple is distributing a TrueType^TM INIT for System 6.0.7, why didn't you put it on the CD of Issue 6? I hope I can find it in the next issue even though System 7.0 is now available.
--Tetsuya Ishikawa

I hope we can fulfill other people's wishes as easily as we did yours. The TrueType INIT for System 6.0.7 is now on the CD in the folder with the System; an oversight kept it off of the last CD.

As with all old System software, we're providing this INIT so you can test your software with it (just in case you've got some as-yet-unupgraded users). When testing with the TrueType INIT, make sure you use it only with System 6.0.7; that's the only System it's designed to work with.

Happy testing,--Caroline Rose

DISAPPOINTING CD
I must admit to being disappointed with the CD-ROM disc that came with Issue 6: Tech Notes "stuck" back in 12/90, no Volume VI of Inside Macintosh , just HyperCard® alone rather than a developer's edition, no System 7.0. Should I expect that my perception that the disc is out-of-touch, out-of-date, and insufficient will be permanent? That is, develop is not really meant to be a real developer-support package for the individual (noncorporate) developer operating on a shoe string? Thanks for any insight you can give me.
--Pete Roberts

I certainly hope your perception that the disc is out-of-touch, out-of-date, and insufficient will not be permanent. We collect and press as much as we can, but because we want subscribers to get develop regularly, we don't hold the presses for software or documentation that isn't quite ready yet, as was the case last time for System 7.0 and Inside Macintosh Volume VI. They're both on this issue's disc. The Tech Notes on Issue 6's disc were actually updated through February 1991. (Well, the stack version was, anyway; the MacWrite® version wasn't, and we apologize for the oversight.)

As for the developer edition of HyperCard, Claris Corporation no longer allows us to distribute it.

We'll continue to do our best to give you the latest, greatest information possible!
--Caroline Rose

WHERE'S LOUELLA?
Congratulations, Caroline, on your new job as Editor-in-Cheek of develop . I hope you have as much fun at it as Louella had.

Thanks for the riddle at the end of your first editorial. We've been scratching our heads over it for a while. The closest thing to a guess we can come up with is that you used either a tablet or some other alternative text entry device. You probably were able to emulate the mouse as well as the keyboard. Why? Perhaps to demonstrate that handicapped people can have access to the Macintosh.

A humble suggestion: I've saved all the CD-ROMs that have come with your magazine ( develop the CD, aka develop , the disc, aka Developer Essentials ). How about designing inserts for the CD cases that some of us keep their CD-ROMs in? Something we could print on thick paper, cut out, and stick in the plastic boxes to label the contents. Keep up the good work!
--Lyle D. Gunderson

P.S. I tried to send mail to Louella at pizzuti1@applelink.apple.com, but your system denied knowing about her. Any help you could give me in addressing e-mail to her would be very much appreciated.

Thanks for the nice letter. I'm having more fun than I've ever had on a job.

Regarding the answer to my riddle: If you've read this issue's editorial, you know by now that you were barking up the right tree. Other readers who replied did not think of access by people with physical limitations.

I hope I've succeeded in doing some consciousness raising here. Your idea about the insert is a good one. We didn't manage to get it onto this issue's disc, but we'll try for next time. It sounds as if you're holding on to all the old discs. If so, be careful about using stuff on them, because we update software and generally attempt to correct the mistakes of the past with each new disc.

Louella decided that there was after all no job as much fun as being editor of develop, so she retired to raise flowers in Holland. Just kidding. You can reach her at louella@applelink.apple.com.
--Caroline Rose

POLES AND FONTS
Two things I'd like to mention after reading Issue 5 (Volume 2, Issue 1):

First, I'm not sure that the answer to the question "What is the difference between North and West?" is completely correct. To my mind, there are two points on the globe from which one would be hard pressed to go further West (or East): the North and South Poles.

Second, may I make a typographic recommendation? Please use Courier for "computer voice" (program listings and the like). Prestige Elite is ugly and too lightweight. The Bitstream ® Courier family has a good regular weight and a bold that would be compatible with your Futura headings.

Oh, and without being too dogmatic, I disagree that a spacious layout is necessarily more effective or attractive.
--Toby Thain

You're right, we mistakenly left out the South Pole. Those PR folks for the North Pole do a really good job at making you forget that the other pole exists at all (especially in December, and that was after all our Winter issue). Thanks for the correction.

I'm not sure I agree that Prestige Elite is ugly, but it does bother me that its hyphen (what's typed for a minus sign in code) is so narrow and its O (Oh) and 0 (zero) are not very easily distinguishable. So in this issue we have indeed switched to Bitstream Courier, which solves these problems and has the right weight.

The beauty of a particular font or layout is surely in the eye of the beholder; I've heard at least as many positive responses as negative ones to the choices we've made for develop. We hope that you and others will keep giving us specific feedback so we'll know what's working and what isn't.
--Caroline Rose

COMMENTS 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 name and company name as well as address and phone number. Letters may be excerpted or edited for clarity (or to make them look like they say what we wish they did). *