New Xcode Tip: Supplying Launch Arguments for Command-Line Programs

I added a tip to the Xcode Tools Tips page on supplying launch arguments for command-line programs from Xcode. This information is tucked away in the excerpt from the Xcode chapter, but it's difficult to find. I saw a question about supplying launch arguments on a message board, and another person emailed me about it. When multiple people have the same question, it makes sense to add a tip so everyone can benefit.

New Xcode Tip: Changing the Executable Name

I added a new tip to the Xcode Tools Tips page on changing the executable name in your Xcode projects. If you don't want to read the whole tip, I can summarize it in one sentence. Change your target's Product name build setting, which is part of the Packaging collection.

New Bundles Article

I have a new article on bundles available. It introduces bundles, focusing on application bundles. After reading the article, you will know how to create a bundle, add files to the bundle, and retrieve files from the bundle.

Leopard Delay a Blessing for Me

Apple did me a favor as a writer by delaying the release of Mac OS X 10.5 from June to October. With a June release I would have had a difficult decision to make: delay updating Xcode Tools Sensei until I finished the OpenGL book, or delay development on the OpenGL book to update the Xcode book. Apple gave me another four months to finish the OpenGL book.

All updates for Xcode 3 and Leopard will come in a new edition of Xcode Tools Sensei. Xcode and Interface Builder are going to have major updates. Trying to juggle Xcode 1.x, 2.x, and 3 in one text would be difficult for me to write and you to read. I also will have to take a bunch of new screenshots so it makes sense to have two versions of the book: the current version that supports Xcode 1.x and 2.x, and a new version specifically for Xcode 3. The electronic edition of the Xcode 3 version would be available at a discount for everyone who has the current version of the book.

Skim PDF Viewer

Skim is a free, open-source PDF viewer for Mac OS X. Mac OS X comes with Preview, which views PDF files, and Adobe Acrobat Reader is freely available so what makes Skim special? Skim has features that make reading technical articles and academic papers easier.

The first of these features is the ability to add notes to a PDF document. It's the electronic equivalent of adding sticky notes to a paper document. When you're reading difficult material, being able to make notes to yourself helps in understanding the material.

A second useful feature is the ability to highlight areas of text by putting a circle or box around it. A third feature is snapshots, which let you keep important pieces of a document in easy reach.

Skim is at version 0.2, which means it's far from a finished product. But if you read a lot of PDF technical articles, you should give Skim a test drive.

Using Saturn on Intel Macs

I read a post on Apple's performance and optimization mailing list that tells you what to do to use Saturn on Intel Macs. This information may be useful to some of you so I am writing about it here.

To use Saturn to profile your code, you must compile your code with either the -pg compiler flag (Generate Profiling Code build setting in Xcode) or the -finstrument-functions compiler flag. The -pg compiler flag is the flag most people use, but Apple hasn't added the support for -pg on Intel Macs yet so using the -pg flag won't allow you to run your code with Saturn on an Intel Mac.

The solution is to use the -finstrument-functions flag to compile your code. I didn't see an Xcode build setting for this flag so you'll have to add the flag to the Other C Flags or Other C++ Flags build setting in Xcode.

I don't have an Intel Mac so I can't test this for myself, but the information came from an Apple engineer so I will assume the information is accurate.

OpenGL Book Progress Report for March 2007

I haven't posted anything about the OpenGL book for a while, but I am writing to let you know I am still working on it. Progress has been excruciatingly slow, which has been very frustrating to me. On the code front, I've been working on the physics code. On the writing front, I have a lot of material written on several chapters, but I still don't have a finished chapter. Whenever I write about something, it brings up several additional topics I have to write about. When I write about those topics, it brings up more things to write about, which makes finishing difficult.

I'm Changing Website Hosts

I have started moving the Me and Mark Publishing website to a new host. Everything should be transferred within the next 1-2 days. Hopefully there won't be any problems. I will add an item to the Latest News section about the switch. If you see the item on the Me and Mark Publishing home page, you're viewing the site with the new host.

Seeing Xcode's Build Errors

When you build an Xcode project, Xcode tells you whether or not the build succeeded. If the build succeeded, that's all you need to know, but if the build failed, you want to know what the errors are so you can fix them. Xcode has two places to look at your errors: the Errors and Warnings smart group and the build results window.

Errors and Warnings Smart Group

In the project window's Groups and Files list, you will see the Errors and Warnings smart group. Select the Error and Warnings group and the project window shows the build errors. Double-clicking an error or warning takes you to the line of code where the error occurred.

Build Results Window



When you need to see more detailed information about your build, use the build results window. Choose Build > Build Results to open the build results window. The build results window has three sections. The top section is the build results, which shows the high-level build steps. The middle section is the build transcript, which shows the low-level steps Xcode takes to build your project. The bottom section is the editor. Selecting an error from the build results or the build transcript shows the line of code in the editor where the error occurred.

Showing the Build Transcript

If you open the build results window for the first time, you won't see the build transcript. The build transcript is initially invisible, and you must tell Xcode to show it. Below the build results are four small buttons. Click the third button to show the build transcript.

Writing C++ Programs on Mac OS X

A frequently asked question on Mac programming forums is "Can I write C++ programs on Mac OS X?". Yes, you can write C++ programs on Mac OS X

Install the Xcode Tools

The Xcode Tools contain everything you need to write Mac OS X applications, including C++ programs. Every copy of Mac OS X contains the Xcode Tools. If you have Mac OS X 10.4, there should be an item called Xcode Tools on the Mac OS X DVD. This item contains the installer. Older versions of Mac OS X that ship on multiple CDs contain either an Xcode Tools or Developer Tools CD.

Apple frequently updates the Xcode Tools so the version that shipped with your copy of Mac OS X is most likely not the most recent version. If you have a broadband Internet connection, I recommend going to Apple's developer page and signing up for a free ADC membership. After signing up for an ADC membership, you can download the most recent version of the Xcode Tools.

One common concern people have when installing the Xcode Tools is the size of the install. The easy install of the Xcode Tools is over 1.5 GB, which is overkill if all you want to do is learn C++. You can perform a custom install of the Xcode Tools to reduce the size of the install. If you are low on disk space, the easiest way to save space is to not install the developer documentation. The developer documentation takes about 1 GB of disk space, and you can view all the documentation online anyway.

Writing Standard C++ Programs

The people most likely to ask if they can write C++ programs on Mac OS X are Mac-using college students who are taking a class on C++ programming. C++ programming classes normally teach standard C++, which will run on most operating systems, including Mac OS X.

To write a standard C++ program with Xcode, you must create a C++ Tool project. C++ Tool projects are used to write command-line programs without a GUI, which makes programming easier. You can read an article on the Xcode Tools Sensei page that contains detailed instructions on creating and building a C++ Tool project.

Writing C++ GUI Programs

After learning C++ you may want to use your newfound knowledge to write Mac OS X GUI programs. You have three options for writing Mac GUI applications in C++. First, you can use Cocoa, writing your user interface code in Objective C and the rest of your code in C++. You must give your Objective C files the extension .mm, which tells Xcode to treat them as Objective C++ files. Objective C++ lets you mix C++ and Objective C code in the same source file.

Second, you can use Carbon, which is Apple's C API for writing GUI applications. If you choose to use Carbon, you may want to look into Nano, an open-source C++ framework built on top of Carbon.

Third, you can use a C++ cross-platform GUI framework like Qt or wxWidgets. I haven't used either of these frameworks, but you should check them out if you are interested in supporting Linux and Windows as well as Mac OS X.