POSIX Threads (pthreads)
Official docs outline
9 sections- pthreads(7)
NPTL overview and thread-safety.
- pthread_create(3)
Creating threads with attributes.
- pthread_mutex_lock(3p)
Mutex types, lock and unlock semantics and error checking mutexes.
- pthread_cond_wait(3p)
Condition variables and spurious wakeups.
- pthread_attr_init(3)
Thread attributes such as stack size.
- pthread_cancel(3)
Cancellation points and cleanup.
- sem_overview(7)
Named and unnamed POSIX semaphores with sem_wait and sem_post.
- pthread_rwlock_rdlock(3p)
Reader-writer locks and writer starvation policy.
- POSIX standard threads
The pthread.h header and its required types and functions in the POSIX standard.
Each section links to the official page. Titles and summaries by Extra Credit; the docs belong to their authors.