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Creating a C Library: Difference between revisions
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Finally, you simply need to assemble your crt0.o, crti.o, and crtn.o files and install them in your system library directory. Your _start function is now able to set up the standard library, call the global constructors, and call exit(main(argc, argv)). Don't forget to call your _fini function in your exit function, or the global destructors won't be run, leading to subtle bugs.
== Implementing ==
Most of this will be up to you. A good place to start are the mem* and str*-functions, as they are mostly independent of syscalls and other library routines and make unit testing a breeze. clang and gcc, being nice compilers, both provide a set of [https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html builtin] functions that can be used to skip implementing some parts. This approach gives you working versions of these functions, with the tradeoff being that this method is compiler-specific to clang and gcc only. While this is probably fine for a kernel, your mileage may vary in userland.
== Standards ==
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