TweetFollow Us on Twitter

November 93 - BAMADA Notes

BAMADA Notes

Robert Lenoil

The October BAMADA meeting featured Eric Anderson, author of Apple's Thread Manager package, and Bo Klintberg, author of Software Framework Association's soon-to-be-released OSL Scripting Components product. (There was a September meeting, but I unfortunately couldn't attend, and therefore can't report on the proceedings.)

Thread Manager

The Thread Manager is a Macintosh system extension that provides for multiple threads of execution within a single application. Multi-threaded is all the rage nowadays: Windows NT does it; OS/2 has been doing it; and like so many other "new" features in desktop computer operating systems, many flavors of UNIX have been doing it for years. Now, thanks to the efforts of Eric Anderson and company, you can use the threads model of programming on the Macintosh too.

A thread is a lightweight task within a process that shares all the process's resources (open files, address space, etc.). Basically, a thread is just a private stack and a saved program counter and registers. As context switches go, switching between two threads is fast. When you have a time consuming task to perform or are doing polled or asynchronous i/o, create a separate thread to perform the activity. Periodically or while waiting for i/o, your thread sleeps to allow other threads to run; this lets your program maintain a responsive user interface without the tedious effort of state machine-based background processing from the main event loop, à la MacApp cohandlers or similar mechanisms.

Version 1.2 of Thread Manager is on Apple's November Developer CD. It is not the thread manager described in issue 6 of Apple's d e v e l o p magazine (that thread manager was unsupported and is now obsolete) but the concepts discussed in that article do apply. It can be shipped with your commercial programs for a nominal licensing fee. Also on the developer CD is Voodoo Monkey, a threads-aware debugger (the Debugger from Jasik Designs also knows about Thread Manager); and a utility package that adds semaphores and other features built on top of the basic Thread Manager API.

Thread Manager supports two styles of thread: cooperative and preemptive. Cooperative threads are scheduled at WaitNextEvent time. The default scheduler calls all runnable cooperative threads in a round robin fashion, with special provision for activating the main thread (the initial thread, which will handle your main event loop) whenever an event is available in the OS event queue. Preemptive threads are preemptively multitasked, which means that they run until they yield to another thread or until their time quantum expires. Preemptive threads must follow the rules for code that executes at interrupt time, namely, they cannot call any trap that can cause memory to be moved and they must not call traps where reentrancy is a concern. Preemptive threads are ideal for porting bulky number crunching algorithms to the Macintosh; without any coding changes the main thread will still get processor time and allow the user interface to operate while the computation occurs in the background. Tom Becker demonstrated this technique to the audience with a thread-based version of FracApp, a program which computes and displays the Mandelbrot set.

Threads Manager does have some limitations. For starters, it is only available for applications; not for desk accessories, INITs, or drivers. Thread switching only occurs when the target application is given time by the Process Manager. Since the Process Manager uses a cooperative multiprocessing model, threads - even preemptive ones - can be kept waiting for indefinite periods of time by unfriendly foreground applications. Last, but not least, Eric Anderson announced that preemptive threads will not be supported for native mode applications on PowerPC Macintoshes. So unless you plan on running your applications on PowerPC only in 680x0 emulation mode, you should not use preemptive threads.

OSL Scripting Components

Bo Klintberg spoke to the BAMADA audience as part of his US tour of MADA affiliates. Bo hails from Sweden, where he is hard at work putting the finishing touches on his AppleEvent/AppleScript support library for MacApp. The package is very complete, with a format modeled after MacApp's. It comes with source code (C++), sample apps, an introductory guide, cookbook, class and method reference, 411 help files, and an OSL Scripting Suite reference. The documentation comes to over three hundred pages. Unlike Ken Ryall's MAScript package, which modifies the MacApp source code to add AppleEvent support to existing MacApp classes, OSL Scripting Components leaves the MacApp code untouched and provides a whole new set of classes for dealing with AppleEvents. There are separate classes for client events (which send requests) and server events (which respond to requests). To support a new AppleEvent, your subclass must override the PrepareMessage and ReplyComplete methods; most of the other work is handled for you.

OSL Scripting Components will come with demo applications for an AppleEvent client, an AppleEvent server, and an AppleScript recordable application. In the future, Bo would like to add handlers for the AppleEvent table and database suites. Personally, I wanted him to hurry up and get back to Sweden so that we could get this package sooner; it looks like a winner for AppleEvent and AppleScript programming in MacApp. Hopefully by the time you read this Software Frameworks Association will have announced availability and pricing.

Next time…

BAMADA meets the first Thursday of each month at 7pm at 4 Infinite Loop in Apple's R&D campus in Cupertino. At the November meeting, members of Apple's MacApp team will discuss the upcoming 3.1 release. Also, Tom Becker will be giving a demonstrations on drag and drop, and show a new class that does it for you with no code additions. If you're interested in speaking at an upcoming meeting, or want to be placed on the mailing list for BAMADA announcements, contact Eric Hanig or Tom Becker at ABI.FC (AppleLink), Eric_Hanig@apldbio.com (Internet), or call 800-874-9869 extension 8902.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Skim 1.4.29 - PDF reader and note-taker...
Skim is a PDF reader and note-taker for OS X. It is designed to help you read and annotate scientific papers in PDF, but is also great for viewing any PDF file. Skim includes many features and has a... Read more
FontExplorer X Pro 6.0.2 - Font manageme...
FontExplorer X Pro is optimized for professional use; it's the solution that gives you the power you need to manage all your fonts. Now you can more easily manage, activate and organize your... Read more
1Password 6.7.1 - Powerful password mana...
1Password is a password manager that uniquely brings you both security and convenience. It is the only program that provides anti-phishing protection and goes beyond password management by adding Web... Read more
Vivaldi 1.9.818.44 - An advanced browser...
Vivaldi is a browser for our friends. In 1994, two programmers started working on a web browser. Our idea was to make a really fast browser, capable of running on limited hardware, keeping in mind... Read more
Vivaldi 1.9.818.44 - An advanced browser...
Vivaldi is a browser for our friends. In 1994, two programmers started working on a web browser. Our idea was to make a really fast browser, capable of running on limited hardware, keeping in mind... Read more
Skim 1.4.29 - PDF reader and note-taker...
Skim is a PDF reader and note-taker for OS X. It is designed to help you read and annotate scientific papers in PDF, but is also great for viewing any PDF file. Skim includes many features and has a... Read more
1Password 6.7.1 - Powerful password mana...
1Password is a password manager that uniquely brings you both security and convenience. It is the only program that provides anti-phishing protection and goes beyond password management by adding Web... Read more
FontExplorer X Pro 6.0.2 - Font manageme...
FontExplorer X Pro is optimized for professional use; it's the solution that gives you the power you need to manage all your fonts. Now you can more easily manage, activate and organize your... Read more
VOX 2.8.24 - Music player that supports...
VOX just sounds better! The beauty is in its simplicity, yet behind the minimal exterior lies a powerful music player with a ton of features and support for all audio formats you should ever need.... Read more
OmniPlan 3.7.1 - Robust project manageme...
With OmniPlan, you can create logical, manageable project plans with Gantt charts, schedules, summaries, milestones, and critical paths. Break down the tasks needed to make your project a success,... Read more

Latest Forum Discussions

See All

Fire Emblem Heroes event announces new m...
As reported yesterday, Nintendo was gearing up a live press event for their popular mobile game,Fire Emblem Heroes. While the stream revealed a lot of new things, the event was entirely in Japanese. Luckily we have a rundown of what was announced... | Read more »
Best games we played this week
Another week, another slate of new mobile games. Although there weren't as many big name releases as last week, there were plenty of unique video game titles that came out that's sure to keep you interested over the weekend. Everything from classic... | Read more »
Olli by Tinrocket (Photography)
Olli by Tinrocket 1.0 Device: iOS iPhone Category: Photography Price: $2.99, Version: 1.0 (iTunes) Description: Get drawn in with Olli by TinrocketOlli instantly turns your everyday moments into hand-drawn art and animations. • Watch... | Read more »
Penarium (Games)
Penarium 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: | Read more »
Fire Emblem Heroes is way more profitabl...
Profits for Nintendo's mobile game Fire Emblem Heroes are apparently impressive enough to beat out other Nintendo titles likeSuper Mario Run, despite having 10 times fewer downloads. [Read more] | Read more »
Classic series Robot Unicorn Attack 3 no...
The classic Adult Swim browser game, Robot Unicorn Attack, branched off into a series of popular mobile games. Now, the latest entry into the series, Robot Unicorn Attack 3, is available for iOS and Android mobile devices. [Read more] | Read more »
Sudoku Sweeper (Games)
Sudoku Sweeper 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: A minimalist mashup of Minesweeper and Sudoku. Logic puzzle perfection. Every row, column and zone contains a bomb and one of... | Read more »
Under Leaves (Games)
Under Leaves 1.0.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0.0 (iTunes) Description: Journey into the forest, the jungle or the depths of the deep blue sea. Find chestnuts for the pigs, a caterpillar for the... | Read more »
Ninja Pizza Girl (Games)
Ninja Pizza Girl 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: In the not-so-distant future, rampart traffic congestion has resulted in only one way to deliver pizzas across town in thirty... | Read more »
SCRAP (Games)
SCRAP 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: That day, for no apparent reason, SCRAP decided to wake up and run. He had to, because his activation was a mistake the "Factory" could... | Read more »

Price Scanner via MacPrices.net

15-inch 2.7GHz Space Gray Touch Bar MacBook P...
B&H Photo has the 15″ 2.7GHz Space Gray Touch Bar MacBook Pro in stock today and on sale for $2599…$200 off MSRP. Shipping is free, and B&H charges NY & NJ sales tax only: - 15″ 2.7GHz... Read more
13-inch 2.9GHz/256GB Space Gray Touch Bar Mac...
B&H Photo has the 13″ 2.9GHz/256GB Space Gray Touch Bar MacBook Pro in stock today and on sale for $150 off MSRP including free shipping plus NY & NJ sales tax only: - 13″ 2.9GHz/256GB Touch... Read more
21-inch iMacs on sale for up to $151 off MSRP
B&H Photo has 21″ iMacs on sale for up to $151 off MSRP, each including free shipping plus NY sales tax only: - 21″ 3.1GHz iMac 4K: $1348 $151 off MSRP - 21″ 2.8GHz iMac: $1199.99 $100 off MSRP... Read more
Weekend deal: Up to $420 off new MacBook Pros...
Apple has Certified Refurbished 2016 15″ and 13″ MacBook Pros available for $230 to $420 off original MSRP. An Apple one-year warranty is included with each model, and shipping is free: - 15″ 2.6GHz... Read more
Price drop: 15-inch 2.2GHz Retina MacBook Pro...
Amazon has dropped their price on 15″ 2.2GHz Retina MacBook Pros (MJLQ2LL/A) to $1709.99 including free shipping. Their price is $290 off MSRP for this model. Note that stock may sell out quickly at... Read more
2.8GHz Mac mini on sale for $899, save $100
B&H Photo has the 2.8GHz Mac mini (model number MGEQ2LL/A) on sale for $899 including free shipping plus NY & NJ sales tax only. Their price is $100 off MSRP. 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 System Clock for macOS by B-Eng Now Avail...
Fehraltorf, Switzerland based B-Eng has announced the release and immediate availability of System Clock, the company’s new system monitor and information app developed exclusively for macOS. System... Read more
DEVONtechnologies Celebrates 15th Anniversary...
DEVONtechnologies celebrates its 15th company anniversary with a 30% discount on all its software products from May 1st through 5th, 2017. In spring 2002, DEVONtechnologies opened its website and... Read more
WaterField Designs Invites Customers to Help...
San Francisco based WaterField Designs invites customers and air travelers to participate in developing the next generation in-flight travel case, the Air Porter. Frustrated with limited legroom,... Read more

Jobs Board

Best Buy *Apple* Computing Master - Best Bu...
**501846BR** **Job Title:** Best Buy Apple Computing Master **Location Number:** 001126-South Bay Center-Store **Job Description:** **What does a Best Buy Apple Read more
Consultant or Sr. Consultant, *Apple* Allia...
…improve our business and your clients will be heard.Project Manager, Apple AllianceLocation:San Francisco preferred, open to other locationsLevel:Consultant or Sr. Read more
*Apple* Mac Computer Technician - GeekHampto...
…complex computer issues over the phone and in person? GeekHampton, Long Island's Apple Premium Service Provider, is looking for you! Come work with our crew Read more
*Apple* Mobile Master - Best Buy (United Sta...
**501505BR** **Job Title:** Apple Mobile Master **Location Number:** 000849-Gurnee-Store **Job Description:** **What does a Best Buy Apple Mobile Master do?** At Read more
Best Buy *Apple* Computing Master - Best Bu...
**498428BR** **Job Title:** Best Buy Apple Computing Master **Location Number:** 000293-Rockville-Store **Job Description:** **What does a Best Buy Apple Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.