PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
enum PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP = _Anonymous_13.PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP;

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