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Ville Juven
e9ef70e24b
POSIX dictates that assert() terminates via abort(), even though in NuttX abort() just calls exit(EXIT_FAILURE) it is better to use the correct API here, if at some point a proper implementation for abort() is made. Also, as the kernel must not use abort() which is a userspace API, direct the exit to PANIC() if for some reason _assert() returns (it should not but trap it here just in case).
README ====== This directory holds NuttX libraries. Libraries in NuttX are very special creatures. They have these properties: 1. They can be shared by both application logic and logic within the OS when using the FLAT build. 2. But in PROTECTED and KERNEL modes, they must be built differently: The copies used by applications and the OS cannot be the same. Rather, separate versions of libraries must be built for the kernel and for applications. 3. When used by the OS, some special care must be taken to assure that the OS logic does not disrupt the user's errno value and that the OS does not create inappropriate cancellation points. For example, sem_wait() is both a cancellation point and modifies the errno value. So within the FLAT build and without kernel version for the PROTECTED and KERNEL builds, the special internal OS interface nxsem_wait() must be used. Within libraries, the macro _SEM_WAIT() (as defined in include/nuttx/semaphore.h) is used instead. The definition of this macro accounts for the different usage environments. NOTE: The libraries under libs/ build differently from other NuttX components: There are no build-related files in the libs/ directory; it is simply a container for other well-known, individual library directories. The upper level Makefile logic is aware of the libraries within the libs/ container. The only real function of the libs/ directory is to prevent the top-level directory from becoming cluttered with individual libraries.