PTHREAD_GETSPECIFIC(3) | Library Functions Manual | PTHREAD_GETSPECIFIC(3) |
pthread_getspecific
,
pthread_setspecific
—
#include <pthread.h>
void *
pthread_getspecific
(pthread_key_t
key);
int
pthread_setspecific
(pthread_key_t
key, const void
*value);
pthread_getspecific
() function returns the value
currently bound to the specified key on behalf of the
calling thread. Conversely, the pthread_setspecific
()
function associates a thread-specific value with a key
obtained via a previous call to
pthread_key_create(3).
Different threads have different values bound to each key. These values are
typically pointers to blocks of dynamically allocated memory that have been
reserved for use by the calling thread.
Undefined behavior may follow if either function is called with a
key value not obtained from
pthread_key_create(3),
or if the call is made after key has been deleted with
pthread_key_delete(3).
It is possible to call either function from a thread-specific data
destructor function. Note however that this is not well defined for the
pthread_setspecific
() function; lost storage or
infinite loops may occur.
pthread_getspecific
() function will return the
thread-specific data value associated with the given
key. If no thread-specific data value is associated with
key, then the value NULL
is
returned. If successful, the pthread_setspecific
()
function will return zero. Otherwise an error number will be returned to
indicate the error.
July 9, 2010 | NetBSD 9.0 |