TweetFollow Us on Twitter

Aug 99 Factory Floor

Volume Number: 15 (1999)
Issue Number: 8
Column Tag: From the Factory Floor

Richard Atwell, Mac OS Debugger

by Richard Atwell and Dave Mark, ©1999 by Metrowerks, Inc., all rights reserved.

This month, we'll hear from Richard Atwell, a key member of Metrowerks' Debugger team. Richard will fill us in on the latest and greatest in Macintosh CodeWarrior debugging.

Richard Alexander David Atwell, aka ratwell, is the Mac OS Debugger Engineer at Metrowerks and is responsible for making MetroNub do nasty things to Mac OS so you can debug your code. Before joining Metrowerks, Richard worked for the Apple Education Consultant Program in Canada. He can be reached at <ratwell@metrowerks.com>.

Dave: Richard, tell me about your role at Metrowerks?

Richard: I work on Mac OS Debugging along with Ken Ryall, our Debugger Architect and our Java debugger engineers. Ken and I are responsible for adding support in CodeWarrior's integrated debugger for emerging Mac OS technologies.

Dave: I know you are working on the debugger for Mac OS X. Tell me about that.

Richard: CodeWarrior runs on Mac OS, Windows, Solaris and now Linux. Before we could deliver a version that ran on Mac OS X, developers needed to be able to debug applications that ran on the new operating system. At the time, the only remote debugger that we had was the Mac->Win debugger that lets you debug targets that run on a Win32 machine from a Mac running the IDE, but there wasn't much that we could reuse for the new OS. So with help from Apple we decided to leverage the debugger built into Mac OS X called gdb.

gdb is the command line debugging tool that is indigenous to UNIX based operating systems like Mac OS X. We discovered that NeXT/Apple had been modifying gdb over the years to meet their own needs but had kept it up to date with the open-source gdb version. All that we needed to do was hide the gdb command line interface from the developer and allow it to be controlled from the IDE.

With Apple's assistance we created a remote debugger for CodeWarrior running on Mac OS 8 that allows you to debug applications on a second Mac running Mac OS X over TCP/IP. gdb is running behind the scenes on Mac OS X but all the developer sees is a simple control panel like application that allows you to set the IP address and port of the machine that is running the IDE and a button to start/stop gdb.

Dave: Tell me about the new Mac OS 8 remote debugger? Is it similar to what Metrowerks did with the Mac->Win cross debugger?

Richard: Yes. For Windows we have an application called MWRemote that is run on the target machine and it acts as the middleman between the IDE running on the host Mac and Windows where your target runs.

For Mac->Mac debugging, we needed to write a similar application to run on the target machine. On the Pro 5 Tools CD in the "Other Metrowerks Tools" folder you'll find an application called MetroNub Remote 2.0. By running this application on a second Mac that has the MetroNub extension installed, you can debug applications remotely.

To operate it, run MetroNub Remote 2.0 and configure it with an IP address and port. This is a necessary security precaution to prevent "unfriendly" IDEs from debugging and essentially running programs on your Mac. Once the remote machine is setup, you configure the IDE for remote debugging by entering an IP address and port in the MetroNub settings preference panel. You next specify the path on the remote machine where the target is to be executed from and you're ready to debug the application just as you would if it were running on the same machine as the IDE.

Dave: What's new with Pro 5's integrated debugger?

Richard: We've added a lot of value to the debugger with Pro 5. The debugger in the IDE has an improved variables view that is better at displaying variable values for the supported languages. There is also a new widget at the top that toggles between two new variable modes: All and Auto. When the widget is toggled from All to Auto the view displays only the variables that are in the scope of the statement block where the program counter lies. Before we added this it was often awkward having to scroll the view down to the bottom to see the variables that you were interested in.

Remote debugging support for Mac OS 8 and Mac OS X is a large addition as we've already mentioned. Remote debugging is advantageous when you are short of screen real estate, wish to debug a system version earlier than the one you usually develop on, debug on another OS, or simply wish to stay independent of the program crashes that can interrupt your development cycle.

Dave: How about remote Java debugging?

Richard: Remote debugging of Java is now possible with Pro 5. In previous releases the MetroNub plug-in was used to debug Mac OS and Java programs. With Pro 5 our Java engineers have created a new debugger plug-in called SunJavaPlugin which uses the debugging facilities built-into Apple's MRJ. Debugging is done over TCP/IP when debugging on a local machine so making it work in the remote case required little extra development effort.

Dave: Is it possible to debug Java on other platforms?

Richard: Yes. Any Java VM that supports Sun's debugger API can be debugged remotely as long as both machines have TCP/IP services. We've also implemented a remote debugger for Win32 that lets you debug from one Win32 machine to another for the first time.

Dave: Aside from remote debugging, what else is new?

Richard: There is now an ability to control whether or not to attempt to automatically debug libraries that your program links against. There is a global setting for this that is used when there isn't a target, such as when you attach to an already running process. There is also a target-level setting to control this behavior.

We've changed the Debugger Setting panel that appears when you edit the preferences of your target. The field which previously specified the location of the host application has been changed to include the location of the remote folder where targets will execute from and also to include the location where code resources, shared libraries or DLLs that are used by your target can be found. The host application field has been relocated to a new panel called Runtime Settings.

We've also improved the reporting of libraries that are loaded by your application. You can now toggle whether the display of library loading messages appear in the log window with a checkbox. Previously this checkbox only applied if you were using the Mac->Win cross debugger.

To improve the debugging experience, there we've added a setting for a delay that can be adjusted which tells the IDE how often to refresh the contents of windows while you are debugging. This can also be set in the Debugger Settings panel.

Dave: How about Mac OS X and Carbon?

Richard: Mac OS X and Carbon are the hot programming topics today. Mac OS X has been making small leaps for about a year now and we've been making similar progress in order to keep from developing solutions with a short life span.

Our ultimate goal is to provide a Carbonized IDE that runs on the client version of Mac OS X. In the meantime we've been providing tools in staged releases.

Dave: What's been done for Carbon developers?

Richard: Carbon is Apple's programming model for Mac OS 8 and Mac OS X that allows developers to leverage the Mac OS toolbox based code they have developed over the last several years. Carbon is the only programming model on Mac OS X that doesn't require developers to completely rewrite their code. This makes Carbon very attractive to developers and we believe that CodeWarrior users are going to choose this development path over the others for most of their development needs.

Towards filling this demand we've been creating the tools that our customers require as the evolving Mac OS X technology allows us.

The first step we took was to release compiler and linker plug-ins with Pro 4 that created binaries in the Mac OS X native Mach-O execution. You could use these to create a separate target in your project that generated a Mach-O binary with which you could move over to Mac OS X and then debug it using gdb.

With the release of Mac OS X PR1 at WWDC this year, Pro 5 took the next logical step and made it possible to use the CodeWarrior integrated debugger for debugging applications on Mac OS X via remote debugging.

The Mac OS X remote debugger setup was specifically designed for debugging Carbon applications. Carbon applications can be PEF based just as they are now for Mac OS 8 or Mach-O based for Mac OS X. If you make applications that are PEF based using the Mac OS PPC Linker instead of the Mach-O linker, you can develop using a single target that you can then debug on Mac OS 8 or remotely on Mac OS X or Mac OS 8. If you app uses shared libraries for plug-ins or for code separation you'll have stick with PEF because Mach-O uses a different scheme for shared libraries that isn't supported by our debugger.

Dave: What's the word on AltiVec support?

Richard: AltiVec is an extension to the PowerPC architecture that provides 32 new 128-bit registers, 162 new instructions and a new execution unit within the AltiVec processor itself to complement the Branch, Integer and Floating Point units.

In addition, Apple and Motorola have introduced an AltiVec programming model for Mac developers in the form of an extension to the C language to support a new variable type called vector.

We've added the language support to our C/C++ compilers and added the necessary ABI changes to the linker. To the debugger, we've added support for displaying vectors variables just as we display any other type and we've added a third register window. Because AltiVec registers as so wide we've implemented a scrolling window to preserve screen real estate.

Dave: What's coming down the road?

Richard: Apple has revisited multi-processing with the introduction of Mac OS 8.6 using the MP hardware introduced a few years ago. For several releases we've had a version of MetroNub that was specifically designed for debugging MP tasks called "MetroNub for MP". Apple has dramatically changed their MP implementation with version 2.0 of the "Multiprocessing API Library" in Mac OS 8.6 and, as a result, the version of MetroNub for MP that shipped with Pro 5 is only compatible with MacOS 8.5.1 and earlier.

We're updating MetroNub for MP to support the new and improved MP library and the update will be available soon.

We're also planning to merge the two versions of MetroNub together. We originally split the extension into two separate versions because the old MP Library 1.4 had a huge memory overhead. Since the new library has a very low overheard of only 100K or so, we can merge the two versions together again. The merged extension will support MP debugging only on Mac OS 8.6 or later. If you want to debug MP Tasks on older versions of the OS, you can still use previous versions of CodeWarrior.

Another request that we've been listening to is to allow remote debugging of Mac applications from the IDE running on Win32 machines. After adding Win->Win and Mac->Mac debugging in Pro 5, we're now working on Win->Mac debugging for the next release. We hope this will encourage Windows developers to port their applications to Mac OS.

Dave: Any other changes on the CodeWarrior CDs?

Richard: We cleaned up the Mac OS Support folder by removing headers and libraries that belong to obsolete SDKs. We've also improved the layout by prominent placement of the OpenTransport and Universal folder that Apple provides. When new versions of these headers and libraries appear between CodeWarrior releases you'll easily be able to replace or add the new headers without having to walk the Mac OS Support folder hierarchy looking for the files that need to be removed.

We've also updated the MPW folder to the latest Tools CD from Apple and of course we've included versions of our MPW tools in that folder.

Finally, we've added a Sherlock index to the reference CD so all HTML and text documents have been searched along with the example code.
 
AAPL
$112.65
Apple Inc.
+3.24
MSFT
$47.52
Microsoft Corpora
+1.78
GOOG
$511.10
Google Inc.
+6.21

MacTech Search:
Community Search:

Software Updates via MacUpdate

BBEdit 11.0.2 - Powerful text and HTML e...
BBEdit is the leading professional HTML and text editor for the Mac. Specifically crafted in response to the needs of Web authors and software developers, this award-winning product provides a... Read more
ExpanDrive 4.2.1 - Access cloud storage...
ExpanDrive builds cloud storage in every application, acts just like a USB drive plugged into your Mac. With ExpanDrive, you can securely access any remote file server directly from the Finder or... Read more
Adobe After Effects CC 2014 13.2 - Creat...
After Effects CC 2014 is available as part of Adobe Creative Cloud for as little as $19.99/month (or $9.99/month if you're a previous After Effects customer). After Effects CS6 is still available... Read more
Command-C 1.1.7 - Clipboard sharing tool...
Command-C is a revolutionary app which makes easy to share your clipboard between iOS and OS X using your local WiFi network, even if the app is not currently opened. Copy anything (text, pictures,... Read more
Tidy Up 4.0.2 - Find duplicate files and...
Tidy Up is a complete duplicate finder and disk-tidiness utility. With Tidy Up you can search for duplicate files and packages by the owner application, content, type, creator, extension, time... Read more
Typinator 6.3 - Speedy and reliable text...
Typinator turbo-charges your typing productivity. Type a little. Typinator does the rest. We've all faced projects that require repetitive typing tasks. With Typinator, you can store commonly used... Read more
GraphicConverter 9.5 - Graphics editor w...
GraphicConverter is an all-purpose image-editing program that can import 200 different graphic-based formats, edit the image, and export it to any of 80 available file formats. The high-end editing... Read more
Toast Titanium 12.0.1 - The ultimate med...
Toast Titanium goes way beyond the very basic burning in the Mac OS and iLife software, and sets the standard for burning CDs, DVDs, and now Blu-ray discs on the Mac. Create superior sounding audio... Read more
QuickBooks 2015 16.0.2.1422 R3 - Financi...
Save 20% on QuickBooks Pro for Mac today through this special discount link QuickBooks Pro 2013 helps you manage your business easily and efficiently. Organize your finances all in one place, track... Read more
Remotix 3.0.6 - Access all your computer...
Remotix is a fast and powerful application to easily access multiple Macs (and PCs) from your own Mac. Features: Complete Apple Screen Sharing support - including Mac OS X login, clipboard... Read more

Latest Forum Discussions

See All

Shift - Photo Filters Designed By You (...
Shift - Photo Filters Designed By You 1.0 Device: iOS Universal Category: Photography Price: $.99, Version: 1.0 (iTunes) Description: | Read more »
Elastic Drums (Music)
Elastic Drums 1.0 Device: iOS iPhone Category: Music Price: $3.99, Version: 1.0 (iTunes) Description: *** Introduction price 3,99$ instead of 7,99$ *** Elastic Drums is a music app with 6 channels of synthesized drum sounds, a step... | Read more »
Fireworks Simulator (Games)
Fireworks Simulator 1.0.8 Device: iOS Universal Category: Games Price: $.99, Version: 1.0.8 (iTunes) Description: *** 50% discount – For a short time only *** You can play Fireworks Simulator on these devices: - iPhone 5, 5s, 5c, 6,... | Read more »
The Hit List — Simply Powerful Tasks, To...
The Hit List — Simply Powerful Tasks, To-Dos, Projects, & Reminders 2.0 Device: iOS iPhone Category: Productivity Price: $9.99, Version: 2.0 (iTunes) Description: >> LAUNCH SPECIAL: The Hit List 2 for iPhone is ONLY $9.99... | Read more »
Mahjong Journey Review
Mahjong Journey Review By Jennifer Allen on December 18th, 2014 Our Rating: :: STEADY MATCHINGiPad Only App - Designed for the iPad Aimed at the more laid back gamer, Mahjong Journey isn’t for everyone, but those looking for some... | Read more »
Emoji Type - custom keyboard with predic...
Emoji Type - custom keyboard with predictive emojis 0.4.0 Device: iOS iPhone Category: Utilities Price: $.99, Version: 0.4.0 (iTunes) Description: Emoji Type is custom keyboard for iOS 8 that auto suggests emojis as you type. ABOUT... | Read more »
Game of the Year 2014 – 148Apps Staff Pi...
The end of 2014 is almost here, which can only mean one thing. Okay it can mean a lot of things, but in this specific context it means Game of the Year lists! Which is why the 148Apps staff have all picked their favorites from the past year. And why... | Read more »
UponPixels Review
UponPixels Review By Jennifer Allen on December 18th, 2014 Our Rating: :: CREATIVE TYPOGRAPHYUniversal App - Designed for iPhone and iPad Add cool typography and objects to your photos with the easy to use UponPixels.   | Read more »
The Vikings are Coming! CastleStorm’s Ne...
The Vikings are Coming! CastleStorm’s New Update Adds a Survival Mode Posted by Jessica Fisher on December 18th, 2014 [ permalink ] | Read more »
Duet Display (Productivity)
Duet Display 0.3.3 Device: iOS Universal Category: Productivity Price: $9.99, Version: 0.3.3 (iTunes) Description: Duet Display allows you to use your iPad or iPhone as an extra display. Developed by a team of ex-Apple engineers,... | Read more »

Price Scanner via MacPrices.net

Save up to $400 on MacBooks with Apple Certif...
The Apple Store has Apple Certified Refurbished 2014 MacBook Pros and MacBook Airs available for up to $400 off the cost of new models. An Apple one-year warranty is included with each model, and... Read more
Save up to $300 on Macs, $30 on iPads with Ap...
Purchase a new Mac or iPad at The Apple Store for Education and take up to $300 off MSRP. All teachers, students, and staff of any educational institution qualify for the discount. Shipping is free,... Read more
iOS and Android OS Targeted by Man-in-the-Mid...
Cloud services security provider Akamai Technologies, Inc. has released, through the company’s Prolexic Security Engineering & Research Team (PLXsert), a new cybersecurity threat advisory. The... Read more
KMI MIDI K-Board Great Gift for Amateur &...
The K-Board is a MIDI Nano keyboard for music creation for iPad, Android, And computers; the easiest way to make music with iPads & Android tablets, and Mac, Windows, or Linux computers. Ultra-... Read more
Amazon offers 15-inch 2.2GHz Retina MacBook P...
 Amazon.com has the 15″ 2.2GHz Retina MacBook Pro on sale for $1699 including free shipping. Their price is $300 off MSRP. Stock is limited, so act now if you’re interested. Read more
Holiday sales continue: MacBook Pros for up t...
 B&H Photo has new MacBook Pros on sale for up to $300 off MSRP as part of their Holiday pricing. Shipping is free, and B&H charges NY sales tax only: - 15″ 2.2GHz Retina MacBook Pro: $1699... Read more
Holiday sale: Mac minis available for up to $...
 B&H Photo has new 2014 Mac minis on sale for up to $80 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 1.4GHz Mac mini: $459 $40 off MSRP - 2.6GHz Mac mini: $629 $70 off... Read more
Google Search App For iOS Gets A Major Makeov...
Google has given iOS users an early Christmas present with a substantial update of it’s not-very-often-upgraded Google Search app. Google Search has been my go-to tool for Web searches since it was... Read more
ShopKeep Apple Pay And Chip Card Reader Avail...
ShopKeep, a cloud-based technology provider to more than 10,000 small business owners to manage retail shops and restaurants with iPads, has released its new Apple Pay and chip card reader. This... Read more
Holiday sale! 27-inch 5K iMac for $2299, save...
 B&H Photo has the 27″ 3.5GHz 5K iMac in stock today and on sale for $2299 including free shipping plus NY sales tax only. Their price is $200 off MSRP, and it’s the lowest price available for... Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Retail - Multiple Positions (US) - A...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Project Manager / Business Analyst, WW *Appl...
…a senior project manager / business analyst to work within our Worldwide Apple Fulfillment Operations and the Business Process Re-engineering team. This role will work Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.