TweetFollow Us on Twitter

Debugging Pascal
Volume Number:2
Issue Number:9
Column Tag:Intermediate Mac'ing

Debugging with LightSpeed Pascal

By David E. Smith, Editor & Publisher

The Boston Expo this week promises to offer a world of new Mac products of particular interest to developers. Many of these products will revolutionize how software is done on the Mac, so it is time to take stock and review the software development process on the Mac.

Where to Begin

The first step in the product development cycle is to get information. This means getting a copy of Inside Macintosh by Addison Wesley, volumes 1-3 and soon volume 4. I prefer the hard bound all in one edition (great for dropping on bugs ). Next some Mac hardware is in order. A Mac Plus with a two meg upgrade from MacMemory is a must. A hard disk, scsi type, is helpful. The DataFrame 20 has been reported as a "safe" buy, reliable, few problems. A new round of 60 to 100 meg drives is also appearing in the $2500 range. Hardware and book in hand, it's time to reach for the check book and buy additional information. Apple's software supplements and technical notes are a must, from Apple's mailing facility. For referencing the ROM, there is TOM's Program's little ROM reference deck. Finally, don't forget the MacTutor subscription!

Utilities are important. No programmer should be without Fedit Plus, Mac Nosy 2.1, TMON or Heap Show. Both Fedit Plus and Mac Nosy 2.1 are new versions being shown at Boston. All four of these products are available from MacTutor as well as other technical software outlets. Heap Show is a very valuable little utility that allows you to analyze heap use in your program, find dangling handles and pointers, and help you prevent heap fragmentation. It is one of the most valuable of utilities yet is also the least known.

Now loaded with documentation from IM, supplements and back issues of MacTutor, the next step is finding out what it all means. For this, the only way to go is to sign up for Dave Wilson's Macintosh Programming Class. This is Apple's official introduction to Mac Programming and it is indispensible. I just finished the class and I really learned a lot about the Mac that I either didn't know or didn't understand correctly. Dave is a master teacher and well versed in the Mac hacker's world. Cost is not cheap at $1,000, but it's well worth the price if your part of a company project. Six months after you're well along in development, thanks to Dave Wilson, you can then sign up for Scott Kanaster's Mac College to get the bugs out of your project. But we're getting ahead of ourselves. First you must decide on a development system.

HFS Changes Development Environment

Under MFS, the Mac supported a number of traditional development systems. The Aztec C 1.06G is preferred by Unix programmers because it preserves much of the Unix flavor of software development within the Mac interface. Consulair C and TML Pascal both present a similar Mac User Interface for software development using the traditional Edit/Compile/Link process. Under MFS, this traditional approach worked fine. However, under HFS, this approach breaks down because development systems must devise various methods of finding include files and trap files now arranged in different directories. The real problem is that HFS really makes the traditional approach of edit, compile and link obsolete. It simply takes too much time to run a program, bomb a program, debug a program, edit, compile, link and try again, when dealing with such a highly interactive and dynamic environment as Macintosh. Servant may ease this problem when available, by bringing a user configurable integrated environment to seperate programs not originally designed to be integrated, making a kind of user constructable LightSpeed environment, with the added advantage that you select the tools to install.

Solving the HFS Problem

The new world of development systems now coming out for the Mac solve the HFS problem by creating a development environment, in which all the files necessary to support the program development cycle is known to the system. These new systems are MPW from Apple, which brings Object Pascal and MacApp in a strong Unix style environment with scripts; TML Pascal 2.0, which also supports Object Pascal and units; and the newest product, LightSpeed C & Pascal, which create a "Project" that bundles files together dramatically speeding up compile and link. Let's focus on LightSpeed Pascal as this product typlifies the new "environment" approach that the Mac interface encourages.

Integrated Tools Speeds Debugging

Mac programming is primarily a process of "discovering" what the Mac ROMS will let you do and how they let you do it. Because of this, re-running programs over and over to experiment is a primary debugging task. With traditional edit, compile and link systems, this process takes several minutes. Make five change and test cycles and you've used up the better part of an hour! With the concept of a "Project", all files are loaded and available, compilation is virtually instant as only the necessary compilation is done, everything else is pre-compiled. Finally, linking is automatic since the project knows both what to link, and what needs to be re-linked after a change. The editing and executing environment are the same, so you can both edit, and execute your program from the same shell, switching back and forth with a click of the mouse between your program's window and menus, and LightSpeed Pascal's windows and menus. Source is always available for editing and source code debugging is fully supported. The result is faster turn-around time in the edit, compile, execute, bomb, re-edit cycle. Instead of several minutes, new attempts are created and tested in seconds. An interactive environment that produces fully compiled double-clickable applications, DA's and drivers.

How it works

The key to LightSpeed Pascal is the project concept. A project is a window and a file that contains a list of all filenames associated with a particular program effort. It also contains compiler and linker information that allows only changed code to be re-compiled and linked dynamically. Since libraries and include files don't have to be re-loaded and compiled as they do on traditional systems, the project approach makes fast turn-around of the compile and link process.

We write a program within our project environment with the LightSpeed Pascal "system". This system includes a multi-file editor. Our editing window is always available, even while our program is running. A build command creates a final application for us that is a fully compiled stand alone program we can move to any disk. For MDS ".REL" files, we can convert them to our project library format with a converter utility, provided. The compiler is fully Lisa and TML Pascal compatible. We compiled last month's keyboard sleuth program without any problem. The system does not have an assembler, so assembly code still must be assembled using MDS or Consulair C systems, and then converted for loading into our project.

The Debugging Process

If your frustrated at trying to marry your development system with MacsBug and TMON, then you'll really appreciate the LightsBug debugging window. Debugging is the key to this system. The system automatically debugs your source code as you type, checking for syntax errors on entry. Instant compilation checks again for normal compilation errors. Finally, running the program again checks for run-time errors. At any time, if an error occurs, you can change the source, look at the debugger window, try some parameter values in the observe window, or change variable values in the instant window. To see what your program is doing, modify the source, set breakpoints and run again. Watch your window while you also watch the debug window! The debug window is automatically linked to the point where your program stopped, showing the heap trail, register values and your global variables. A single click on a global variable, and bang! The debugger shows you a hex and ascii memory dump at the location of the variable.

Figure 1 shows the many windows of LightSpeed Pascal. Our own program window is also available! The project window lists our library, source and include files. Compiler options are set for each file by clicking in the box next to the file name. We change the link order for our project by simply dragging the file name up or down in the project window. No more editing of a link file!

Our source code is shown in another window, and we can open a window for each of our source segments. The observe window allows us to monitor the value of a variable as our program executes. The Instant window allows us to execute program source code or trap calls instantly to observe their effects. If we get what we want, we can paste the line into our source window. Text and drawing have the same purpose they did under MacPascal, but even more important, our own toolbox created windows from our running program are available and clickable along with each of the other windows shown in figure 1.

In figure 2, we see how the observe window works. Here, we've placed a breakpoint at the putstring(s) statement in the source window. After running, our program is now stopped at the break, and the value of s is shown in bold in the observe window. Note that in the LightsBug window, we instantly have the base address of the variable s and can observe it's value in both hex and ascii.

In figure 3, we now change the value of s in the instant window. As we do this, the observe window shows the new value of S, and the LightsBug window shows the new hex and ascii values for s in memory.

In figure 5, we now wish to change the value that is assigned to s directly in memory where our source code lives. We do this by clicking edit and another little debug dialog box opens allowing us to enter a new value directly into memory. As we do this, the LightsBug window shows that what used to be "there!" is now "fere!". This also changes our source code and when we run the program, as figure 6 shows, the new source code value is shown being assigned to s during execution.

Figure 7 shows that our program window exists along with LightSpeed Pascal's windows and we can swtich back and forth by clicking on the spray can (for debugging!).

Finally a Decent Manual

For some reason, Mac development systems have shipped with manuals that assume you already know every language command by heart. Very few even have a simple language definition. If you don't already know C or Pascal, forget it! The LightSpeed manuals are very well done, very large and provide a clear description of the language syntax and commands much like normal manuals on other computers have traditionally done. It is a mystery to me why it has taken this long for decent manuals to be shipped with Mac development environments.

Reaction

I personally think these products will revolutionize how software is done on the Mac. The time saved in testing and re-running programs under development is so tremendous that no one will settle for the large development time required of traditional edit, compile, and link systems. The Mac takes more time anyway in the learning curve of the ROM functions, so anything we can gain in the development cycle is extremely important. But most of all, LightSpeed Pascal will be very popular because no one will want to live without source level debugging with LightsBug if they don't have to. The debugging capabilities will cause people to stop and think if they really need all the overhead of MPW after all.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Macs Fan Control 1.3.1.0 - Monitor and c...
Macs Fan Control allows you to monitor and control almost any aspect of your computer's fans, with support for controlling fan speed, temperature sensors pane, menu-bar icon, and autostart with... Read more
NetShade 6.3.1 - Browse privately using...
NetShade is an anonymous proxy and VPN app+service for Mac. Unblock your Internet through NetShade's high-speed proxy and VPN servers spanning seven countries. NetShade masks your IP address as you... Read more
Dragon Dictate 4.0.7 - Premium voice-rec...
With Dragon Dictate speech recognition software, you can use your voice to create and edit text or interact with your favorite Mac applications. Far more than just speech-to-text, Dragon Dictate lets... Read more
Persecond 1.0.2 - Timelapse video made e...
Persecond is the easy, fun way to create a beautiful timelapse video. Import an image sequence from any camera, trim the length of your video, adjust the speed and playback direction, and you’re done... Read more
GIMP 2.8.14p2 - Powerful, free image edi...
GIMP is a multi-platform photo manipulation tool. GIMP is an acronym for GNU Image Manipulation Program. The GIMP is suitable for a variety of image manipulation tasks, including photo retouching,... Read more
Sandvox 2.10.2 - Easily build eye-catchi...
Sandvox is for Mac users who want to create a professional looking website quickly and easily. With Sandvox, you don't need to be a Web genius to build a stylish, feature-rich, standards-compliant... Read more
LibreOffice 5.0.1.2 - Free, open-source...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
f.lux 36.1 - Adjusts the color of your d...
f.lux makes the color of your computer's display adapt to the time of day, warm at night and like sunlight during the day. Ever notice how people texting at night have that eerie blue glow? Or wake... Read more
VirtualBox 5.0.2 - x86 virtualization so...
VirtualBox is a family of powerful x86 virtualization products for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers... Read more
File Juicer 4.43 - Extract images, video...
File Juicer is a drag-and-drop can opener and data archaeologist. Its specialty is to find and extract images, video, audio, or text from files which are hard to open in other ways. In computer... Read more

ReBoard: Revolutionary Keyboard (Utilit...
ReBoard: Revolutionary Keyboard 1.0 Device: iOS Universal Category: Utilities Price: $1.99, Version: 1.0 (iTunes) Description: Do everything within the keyboard without switching apps! If you are in WhatsApp, how do you schedule a... | Read more »
Tiny Empire (Games)
Tiny Empire 1.1.3 Device: iOS Universal Category: Games Price: $2.99, Version: 1.1.3 (iTunes) Description: Launch cannonballs and blow tiny orcs into thousands of pieces in this intuitive fantasy-themed puzzle shooter! Embark on an... | Read more »
Astropad Mini (Productivity)
Astropad Mini 1.0 Device: iOS iPhone Category: Productivity Price: $4.99, Version: 1.0 (iTunes) Description: *** 50% off introductory price! ​*** Get the high-end experience of a Wacom tablet at a fraction of the price with Astropad... | Read more »
Emo Chorus (Music)
Emo Chorus 1.0.0 Device: iOS Universal Category: Music Price: $1.99, Version: 1.0.0 (iTunes) Description: Realistic Choir simulator ranging from simple Chorus emulation to full ensemble Choir with 128 members. ### introductory offer... | Read more »
Forest Spirit (Games)
Forest Spirit 1.0.5 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0.5 (iTunes) Description: | Read more »
Ski Safari 2 (Games)
Ski Safari 2 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: The world's most fantastical, fun, family-friendly skiing game is back and better than ever! Play as Sven's sister Evana, share... | Read more »
Lara Croft GO (Games)
Lara Croft GO 1.0.47768 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.47768 (iTunes) Description: Lara Croft GO is a turn based puzzle-adventure set in a long-forgotten world. Explore the ruins of an ancient... | Read more »
Whispering Willows (Games)
Whispering Willows 1.23 Device: iOS Universal Category: Games Price: $4.99, Version: 1.23 (iTunes) Description: **LAUNCH SALE 50% OFF** - Whispering Willows is on sale for 50% off ($4.99) until September 9th. | Read more »
Calvino Noir (Games)
Calvino Noir 1.1 Device: iOS iPhone Category: Games Price: $3.99, Version: 1.1 (iTunes) Description: The film noir stealth game. Calvino Noir is the exploratory, sneaking adventure through the 1930s European criminal underworld.... | Read more »
Angel Sword (Games)
Angel Sword 1.0 Device: iOS Universal Category: Games Price: $6.99, Version: 1.0 (iTunes) Description: Prepare to adventure in the most epic full scale multiplayer 3D RPG for mobile! Experience amazing detailed graphics in full HD.... | Read more »

Price Scanner via MacPrices.net

iPad Air 2 on sale for up to $100 off MSRP
Best Buy has iPad Air 2s on sale for up to $100 off MSRP on their online store for a limited time. Choose free shipping or free local store pickup (if available). Sale prices available for online... Read more
MacBook Airs on sale for $100 off MSRP
Best Buy has MacBook Airs on sale for $100 off MSRP on their online store. Choose free shipping or free local store pickup (if available). Sale prices for online orders only, in-store prices may vary... Read more
Big Grips Lift Handle For iPad Air and iPad A...
KEM Ventures, Inc. which pioneered the extra-large, super-protective iPad case market with the introduction of Big Grips Frame and Stand in 2011, is launching Big Grips Lift featuring a new super-... Read more
Samsung Launches Galaxy Tab S2, Its Most Powe...
Samsung Electronics America, Inc. has announced the U.S. release of the Galaxy Tab S2, its thinnest, lightest, ultra-fast tablet. Blending form and function, elegant design and multitasking power,... Read more
Tablet Screen Sizes Expanding as iPad Pro App...
Larger screen sizes are gaining favor as the tablet transforms into a productivity device, with shipments growing 185 percent year-over-year in 2015. According to a new Strategy Analytics’ Tablet... Read more
Today Only: Save US$50 on Adobe Elements 13;...
Keep the memories. lose the distractions. Summer’s winding down and it’s time to turn almost perfect shots into picture perfect memories with Elements 13. And get the power to edit both photos and... Read more
1.4GHz Mac mini on sale for $449, save $50
Best Buy has the 1.4GHz Mac mini on sale for $50 off MSRP on their online store. Choose free shipping or free local store pickup (if available). Price for online orders only, in-store price may vary... Read more
12-inch 1.1GHz Gold MacBook on sale for $1149...
B&H Photo has the 12″ 1.1GHz Gold Retina MacBook on sale for $1149.99 including free shipping plus NY sales tax only. Their price is $150 off MSRP, and it’s the lowest price available for this... Read more
27-inch 3.3GHz 5K iMac on sale for $1849, sav...
Best Buy has the 27″ 3.3GHz 5K iMac on sale for $1849.99. Their price is $150 off MSRP, and it’s the lowest price available for this model. Choose free shipping or free local store pickup (if... Read more
Worldwide Tablet Shipments Expected to Declin...
Does Apple badly need a touchscreen convertible/hybrid laptop MacBook? Yes, judging from a new market forecast from the International Data Corporation (IDC) Worldwide Quarterly Tablet Tracker, which... Read more

Jobs Board

*Apple* Music, Business Operations - Apple (...
**Job Summary** This role in Apple Music and in iTunes is working with…the songs that we all enjoy listening to in Apple Music. Your job will be to work wit Read more
Hardware Systems Integration Engineer - *App...
**Job Summary** We are seeking an enthusiastic electrical engineer for the Apple Watch team. This is a design engineering position that entails working with Read more
Engineering Project Manager - *Apple* TV -...
**Job Summary** The iTunes Apps project management team oversees iTunes, Apple TV, DRM and iOS Applications. We are looking for a project manager to help manage and 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 Online Store: Customer Insigh...
**Job Summary** Apple Retail (Online Store) is seeking an experienced e-commerce analytics professional to join the Customer Insights Team. The Web e-Commerce Analyst Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.