NAME

threads_into — introduction to the Adelsbach Enhanced Threading Library

SYNOPSIS

library “threads”
#include <threads.h>
#include <threadse.h>

DESCRIPTION

The Adelsbach Enhanced Threading Library aims to implement a conform C11 (ISO/IEC 9899:2011) threading interface on top the standard POSIX threading API (IEEE Std 1003.1c-1995). It furthermore implements extensions to the former for spinlocks, read/write locks and thread barriers.

The C11 standard functions are declared in the threads.h header file, whereas all extensions are declared in the threadse.h header file.

The following functionality is supported:

Threading

These implement the standard threading functions.

thrd_create(3) thrd_exit(3) thrd_current(3) thrd_detach(3) thrd_join(3) thrd_equal(3) thrd_sleep(3) thrd_yield(3)

Mutexes

Mutexes will stall a thread until an exclusive lock on the mutex can be acquired.

mtx_init(3) mtx_destroy(3) mtx_lock(3) mtx_timedlock(3) mtx_trylock(3) mtx_unlock(3)

Condition variables

Condition variables will stall a single or multiple threads until a condition has been send out by an other thread. By comparison to a mutex multiple threads can continue execution after the condition has been given.

cnd_init(3) cnd_destroy(3) cnd_broadcast(3) cnd_signal(3) cnd_wait(3) cnd_timedwait(3)

Thread-local storage

Thread-local storage allocates global variables with data specific to each thread.

tss_create(3) tss_delete(3) tss_get(3) tss_set(3)

Call once

This synchronization primitive allows only a single thread to execute a specified function exactly once.

call_once(3)

Read/Write Locks

Read/Write locks allow synchronization for read/write operations. Threads can hold either read or write locks, multiple read locks can be held by multiple threads but only one write lock can be held at a time. The write lock can only be acquired if no read locks are acquired, the read lock can only be acquired once there is no write lock acquired.

rwmtx_init(3) rwmtx_destroy(3) rwmtx_rdlock(3) rwmtx_wrlock(3) rwmtx_tryrdlock(3) rwmtx_trywrlock(3) rwmtx_timedrdlock(3) rwmtx_timedwrlock(3) rwmtx_unlock(3)

Spinlocks

Spinlocks are fast mutexes, that loop on an atomic variable rather than yielding the thread. They are more lightweight than a normal mutex and are suitable for short synchronizations that will not require much wait.

smtx_init(3) smtx_destroy(3) smtx_lock(3) smtx_unlock(3) smtx_trylock(3)

Barriers

Barriers allow for synchronization of thread groups. A barrier will stop all threads upon entering the barrier until a specified amount of threads is waiting, after which execution continues.

bar_init(3) bar_destroy(3) bar_wait(3)

SEE ALSO

pthreads(3)

AUTHORS

Jan Adelsbach <jan@jadelsbach.de>