Home Questions Tags Users Unanswered. This package is intended for linux use though, and I'm on a mac. I didn't know macs were used to universally run all programs. Rob, what I meant was: Now suppose an application wants to override the use of libbar with a compressed version, called libzbar.
Since libfoo was linked against libbar at compile time, this is not possible without recompiling libfoo. The ld man page has a more detailed discussion of this flag. If you are writing libraries from scratch, it may be worth considering the two-level namespace issue in your design. Alternately, you might use a plug-in architecture in which the calls to the outside library are made from a plug-in that could be easily replaced with a different plug-in for a different outside library.
See Dynamic Libraries and Plug-ins for more information. This is usually not necessary, however.
Some bridging tools are provided for classic Macintosh executable formats, but Mach-O is the native format. Dynamic libraries and plug-ins behave differently in OS X than in other operating systems. This section explains some of those differences. If you have a library called libmytool. As a general rule, you should avoid creating static libraries.
You must run ranlib on any archive file before you attempt to link against it.
OS X makes heavy use of dynamically linked code. Unlike other binary formats such as ELF and xcoff, Mach-O treats plug-ins differently than it treats shared libraries. The preferred mechanism for dynamic loading of shared code, beginning in OS X v These are described in the man page for dlopen. This is because OS X has a single dynamically loadable framework, libSystem , that contains much of the core system functionality.
The libSystem library also includes functions that you would normally expect to find in libc and libm , RPC services, and a name resolver.
Sep 27, Building on Linux. Prerequisites. All requisites should be available for your distribution. The most important are: The basic program build tools. Unix is not GNU/Linux and therefore not all programs will compile that with your Mac if it's an older one); Download the NEAT source code.
For your convenience, many of these libraries exist as symbolic links to libSystem , so while explicitly linking against -lm for example is not needed, it will not cause an error. To learn more about how to use dynamic libraries, see Dynamic Library Programming Topics. For the most part, you can treat dynamic libraries and plugins the same way as on any other platform if you use GNU libtool. For more information, see the manual page for glibtool. You can also create dynamic libraries and plugins manually if desired.
Thus, you must pass different flags when you create them. Because plugins can be tailored to a particular application, the OS X compiler provides the ability to check these plugins for loadability at compile time.
If the compiler finds symbol requests in the plugin that cannot be resolved in the application, you will get a link error. This means that you must use the -l flag to link against any libraries that the plugin requires as though you were building a complete executable. To learn more about how to create and use dynamic libraries, see Dynamic Library Programming Topics. In the OS X file system, some directories store executable code and the software resources related to that code in one discrete package.
These packages, known as bundles, come in two varieties: There are two basic types of bundles that you should be familiar with during the basic porting process: In particular, you should be aware of how to use frameworks, since you may need to link against the contents of a framework when porting your application. Application bundles are special directories that appear in the Finder as a single entity. Having only one item allows a user to double-click it to get the application with all of its supporting resources. If you are building Mac apps, you should make application bundles.
Xcode builds them by default if you select one of the application project types. More information on application bundles is available in Bundles vs. Installers and in Mac Technology Overview. A framework is a type of bundle that packages a shared library with the resources that the library requires. Depending on the library, this bundle could include header files, images, and reference documentation.
If you are trying to maintain cross-platform compatibility, you may not want to create your own frameworks, but you should be aware of them because you might need to link against them. For example, you might want to link against the Core Foundation framework. A more thorough discussion of frameworks is in Mac Technology Overview. You can find additional information about bundles in Mac Technology Overview. A multiply defined symbol error occurs if there are multiple definitions for any symbol in the object files that you are linking together.
You can specify the following flags to modify the handling of multiply defined symbols under certain circumstances:. The values for treatment must be one of:. An unused multiply defined symbol is a symbol defined in the output that is also defined in one of the dynamic libraries, but in which but the symbol in the dynamic library is not used by any reference in the output.
The values for treatment must be error , warning , or suppress. The default for unused multiply defined symbols is to suppress these messages. This macro is defined when your code is being compiled by the Objective-C compiler. By default, this occurs when compiling a. You can force the Objective-C compiler to be used for a. This macro is defined on systems that use natural alignment. When using natural alignment, an int is aligned on sizeof int boundary, a short int is aligned on sizeof short boundary, and so on.
It is defined by default when you're compiling code for PowerPC architecutres. It is not defined when you use the -malign-mac68k compiler switch, nor is it defined on Intel architectures. This macro is set to an integer that represents the version number of the compiler. This lets you distinguish, for example, between compilers based on the same version of GCC, but with different bug fixes or features.
Larger values denote later compilers. These macros tell whether the current architecture uses little endian or big endian byte ordering. This file does not exist in OS X, but the functionality does exist. You should include stdlib. Alternatively, you can define the prototypes yourself as follows:. The ftw function traverses through the directory hierarchy and calls a function to get information about each file.
However, there isn't a function similar to ftw in fts.
Alternatively, you can use opendir , readdir and closedir with recursion to achieve the same result. See the manual page for fts to understand the structures and macros used in the code. The sample code above shows a very simplistic file traversal. For instance, it does not consider possible subdirectories existing in the directory being searched.
In OS X, you can use mmap to map files into memory. The modules themselves must be compiled against the Kernel framework. For more information, see IOKit Fundamentals. The implementation of pseudo-TTYs is very different from Linux. For more information, see the pty manual page. OS X does not support this header file.
Home Questions Tags Users Unanswered. This will not work. The OSX kernel is somewhat different from a Linux kernel. Well OS X does not use elf binaries, so it's a bit like trying to run windows. However, a brief search finds this: XBinary requires a program that knows how to run your binary; it in and of itself doesn't run anything. To update the tools, see this post on StackOverflow. The tools are OS Version dependant, ie they are not backwards compatible , to my knowledge in short, don't install XCode for Having installed XCode you now have a compiler, and can head on over to the MacPorts page and browse for the port you need installed, after installing the MacPorts.