C is one of the most used programming languages, many libraries were created to be used with C. Frequently, in the invention of a data format, a C software library or reference is the format for handling. This is the case for libjpeg, libpng, libsocket, Expat, the reference decoder MPEG, etc.
This could restrict all practical portability of programs that need to use some of these features, without the existence of many portable libraries and overcoming this deficiency, in the UNIX world.
Generating an executable as part of Apple Repair Services from the source files is done in several steps, which are often automated using tools, such as make, SCons (written in Python) or even specific tools for integrated development environment (IDE). Steps leading to source executable file are four in number: precompiling, compiling, assembling, linking.