Thread support library

If the macro constant __STDC_NO_THREADS__(C11) is defined by the compiler, the header <threads.h> and all of the names listed here are not provided.

Threads

Defined in header <threads.h>
thrd_t	implementation-defined complete object type identifying a thread
thrd_create (C11)	creates a thread (function)
thrd_equal (C11)	checks if two identifiers refer to the same thread (function)
thrd_current (C11)	obtains the current thread identifier (function)
thrd_sleep (C11)	suspends execution of the calling thread for the given period of time (function)
thrd_yield (C11)	yields the current time slice (function)
thrd_exit (C11)	terminates the calling thread (function)
thrd_detach (C11)	detaches a thread (function)
thrd_join (C11)	blocks until a thread terminates (function)
thrd_successthrd_timedoutthrd_busythrd_nomemthrd_error (C11)	indicates a thread error status (constant)
thrd_start_t (C11)	a typedef of the function pointer type int(*)(void*), used by thrd_create (typedef)

Mutual exclusion

Defined in header <threads.h>
mtx_t	mutex identifier
mtx_init (C11)	creates a mutex (function)
mtx_lock (C11)	blocks until locks a mutex (function)
mtx_timedlock (C11)	blocks until locks a mutex or times out (function)
mtx_trylock (C11)	locks a mutex or returns without blocking if already locked (function)
mtx_unlock (C11)	unlocks a mutex (function)
mtx_destroy (C11)	destroys a mutex (function)
mtx_plainmtx_recursivemtx_timed (C11)(C11)(C11)	defines the type of a mutex (enum)
Call once
call_once (C11)	calls a function exactly once (function)

Condition variables

Defined in header <threads.h>
cnd_t	condition variable identifier
cnd_init (C11)	creates a condition variable (function)
cnd_signal (C11)	unblocks one thread blocked on a condition variable (function)
cnd_broadcast (C11)	unblocks all threads blocked on a condition variable (function)
cnd_wait (C11)	blocks on a condition variable (function)
cnd_timedwait (C11)	blocks on a condition variable, with a timeout (function)
cnd_destroy (C11)	destroys a condition variable (function)

Thread-local storage

Defined in header <threads.h>
thread_local (C11)	thread local type macro (keyword macro)
tss_t	thread-specific storage pointer
TSS_DTOR_ITERATIONS (C11)	maximum number of times destructors are called (macro constant)
tss_dtor_t	function pointer type void(*)(void*), used for TSS destructor
tss_create (C11)	creates thread-specific storage pointer with a given destructor (function)
tss_get (C11)	reads from thread-specific storage (function)
tss_set (C11)	write to thread-specific storage (function)
tss_delete (C11)	releases the resources held by a given thread-specific pointer (function)

Reserved identifiers

Function names, type names, and enumeration constants that begin with either cnd_, mtx_, thrd_, or tss_, and a lowercase letter may be added to the declarations in the <threads.h> header in future revisions of the C standard, and portable programs should not use those identifiers.

References

• C11 standard (ISO/IEC 9899:2011):
• 7.26 Threads <threads.h> (p: 376-387)
• 7.31.15 Threads <threads.h> (p: 456)

See also