Will this do what you want?open -a Preview.app <file>.pdfIf Preview.app is your default reader for pdf files on your system, you should be able to useopen <file>.pdf

Even the abstract class header file will have to be included in something in some chain of files that is eventually included in one or more source files. Not sure what you mean by a "standalone header file." I think in order to build the indexing database, the clang compiler is actually invoked to do static analysis on the source files. Header files to have to be eventually included in at least one source file in order to be compiled. clang/clang++ does not compile header files except when building module map files, but, they are not part of the static analysis.The #include directive is only a pre-processing directive. It allows the compiler to "cut-and-paste" code as part of the compilation process, but, it has to be compiling a source file (or .pch file, which can be considered a source file) in order to do the cutting and pasting.

You need to elaborate a little more about your setup.1 - Use clang. The gcc that is part of the Xcode command line tools is actually a wrapper around clang/llvm. Probably going away in the near future. Plus, that version of gcc is stopped at 4.2.1, because of the adoption of the GNU V3 license by the Free Software Foundation. Apple refuses to use GNU V3 licensed software anymore.2 - Why does the internet have anything to do with compiling source code on your Mac? What terminal program are you using? If you are using the Terminal.app, located in /Applications/Utilities, doesn't require an Internet connection at all. If you are using Xterm with XQuartz, still shouldn't be a problem if you are using it on a local machine.3 - Just compiled a test program for Objective-C with gcc, same setup as yours. Build an object file faster than I could time. More lines of code than hello world.

Mounting a volume is a privileged process on MacOS, and requires that you authenticate yourself to the system, just like sudo.

You might want to look at xcframeworks

When you create a new Run Script, you can move it between any pre-defined steps. Create the new Run Script, click, hold, and drag it in between the Compile Files step, and the Link Library step.

You are, more or less, essentially multiplying and dividing by the same value ( e.g., width * (53 / width) ). The actual result will probably be about 53 +/- 1 regardless of the width. So, you are essentially putting the lower corner of the frame at the same offset in the view, regardless of the size of the screen. You need to take the width, subtract the width of the frame, divide by 2, and use that as the x-value of your offset, if you want to center it horizontally.You are giving explicit screen coordinates on where to place the frame, essentially (53,172) because multiplication and division by the same quantity yields about 1. So, UIKit is putting it where you told it to. Doesn't adjust based on screen size. You have to adjust for screen size, and your math isn't doing that.Autolayout can be done manually, rather than through IB, but, that's a whole different topic.

Bison and Flex are supported already in Xcode. There are several tutorials on how to use the built-in compilers on the Internet, including using later versions than the one supplied with Xcode. Search "Using bison with Xcode", for example.

You probably also have to make Customer and Contractor classes, not structs. This whole architecture looks like it needs reference types, not value types. If you want to assign an instance of Customer to UserData.account, it has to be a sub-class of AProfile.

You need to omit the braces.When you say "preprocessor macros", are you setting up a user-defined environment build setting, or are you actually assigning values to the "Preprocessor Macros" build setting? If it's the latter, I don't think pre-processor macro definitions are available to run scripts except through the GCC_PREPROCESSOR_MACROS environment variable which is set from the build settings. If you are setting the value for "myflag" in the build settings via the GCC_PREPROCESSOR_MACROS (the "Preprocessor Macros" build setting), you'll have to parse the whole macro definition to find "myflag"You can set user-defined environment variables for Xcode via .xcconfig files (look up "xcconfig" files in Xcode documentation, and/or the Internet).

The Xcode debug section is covered at a basic level in the Xcode Help reference accessed via the Xcode Help menu item. The LLDB debugger (the program Xcode shows in the console window when you start debugging) is documented at lldb.llvm.org . There are third party books about Xcode development out there. If you need help with the Swift language, there is swift.org or the "Swift Language Reference" in the Apple bookstore (it's free).

Note that in your loop in main, you are taking the sin/cos of 360 radians, incrementing by 1 radian each cycle. 1 radian is little over 57.0 degrees. All trig functions in the standard library take radians, not degrees, as the measure of an angle.

You'll have to look at the build settings for this package and figure out what settings are different between Release and Debug. I would concentrate on differences in optimization settings, and, if there are C/C++/Objective-C components, you might want to look at the preprocessor macros, but any differences between the Release and Debug build settings should be investigated.Once you figured out what the significant differences between Release and Debug are for the package in question, you need to change the Debug settings to match the relevant Release settings. I would be careful about this, or give yourself some means by which you can go back to the Debug setting if you ever have to debug this package. Some optimizations commonly used to speed up Release speeds do a lot of code restructuring that makes it extremely difficult to debug, if there is a problem.You can change the settings manually, or you can put the changes in an .xcconfig file. Note that if you ever end up upgrading the package to a new version, you will need to re-apply the build setting changes. If you use an .xcconfig file to record the changes, you can store that .xcconfig in your project workspace, and re-apply it after the package gets updated.I'm assuming that the package manifest is not under your control. If you have control over the manifest file contents, there is potential in the .unsafeFlags methods for the swiftSettings/cSettings/cxxSettings method in the target descriptions, but, as the name applies, these are considered unsafe by the SPM builders and maintainers, and there are restrictions on the use of these methods.

Apple does, just not like you do.Why should it be an iPhone 11 Pro? Why not a iPhone 11? An iPhone 8?

You might want to look at the Apple documentation on Key Events to get a general overview of how key events and keyboard processing works. You also need to look at NSResponder keyDown and keyUp methods. A text field is derived from a view which is derived from NSResponder, so, you will override those methods to handle your custom textfield processing.