The pthread_key_delete() function deletes a thread-specific data key previously returned by pthread_key_create(). The thread-specific data values associated with key need not be NULL at the time pthread_key_delete() is called. It is the responsibility of the application to free any application storage or perform any cleanup actions for data structures related to the deleted key or associated thread-specific data in any threads; this cleanup can be done either before or after pthread_key_delete() is called. Any attempt to use key following the call to pthread_key_delete() results in undefined behaviour.

The pthread_key_delete() function is callable from within destructor functions. No destructor functions will be invoked by pthread_key_delete(). Any destructor function that may have been associated with key will no longer be called upon thread exit.

If successful, the pthread_key_delete() function returns 0. Otherwise, an error number is returned to indicate the error.

The pthread_key_delete() function may fail if:

EINVAL

The key value is invalid.

The pthread_key_delete() function will not return an error code of EINTR.

See attributes(5) for descriptions of the following attributes:

pthread_key_create(3THR), attributes(5), standards(5)