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pthread_getspecific(3) [netbsd man page]

PTHREAD_GETSPECIFIC(3)					   BSD Library Functions Manual 				    PTHREAD_GETSPECIFIC(3)

NAME
pthread_getspecific -- thread-specific data value LIBRARY
POSIX Threads Library (libpthread, -lpthread) SYNOPSIS
#include <pthread.h> void * pthread_getspecific(pthread_key_t key); int pthread_setspecific(pthread_key_t key, const void *value); DESCRIPTION
The 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). Differ- ent 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 func- tion. Note however that this is not well defined for the pthread_setspecific() function; lost storage or infinite loops may occur. RETURN VALUES
The 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. Other- wise an error number will be returned to indicate the error. ERRORS
No errors are defined for either function. SEE ALSO
pthread_key_create(3) STANDARDS
These functions conform to IEEE Std 1003.1-2001 (``POSIX.1''). BSD
July 9, 2010 BSD

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pthread_getspecific(3C) 				   Standard C Library Functions 				   pthread_getspecific(3C)

NAME
pthread_getspecific, pthread_setspecific - manage thread-specific data SYNOPSIS
cc -mt [ flag... ] file... -lpthread [ library... ] #include <pthread.h> int pthread_setspecific(pthread_key_t key, const void *value); void *pthread_getspecific(pthread_key_t key); DESCRIPTION
The pthread_setspecific() function associates a thread-specific value with a key obtained by way of a previous call to pthread_key_cre- ate(). Different threads may bind different values to the same key. These values are typically pointers to blocks of dynamically allocated memory that have been reserved for use by the calling thread. The pthread_getspecific() function returns the value currently bound to the specified key on behalf of the calling thread. The effect of calling pthread_setspecific() or pthread_getspecific() with a key value not obtained from pthread_key_create() or after key has been deleted with pthread_key_delete() is undefined. Both pthread_setspecific() and pthread_getspecific() may be called from a thread-specific data destructor function. However, calling pthread_setspecific() from a destructor may result in lost storage or infinite loops. RETURN VALUES
The pthread_getspecific() function returns 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. Upon successful completion, the pthread_setspecific() function returns 0. Otherwise, an error number is returned to indicate the error. ERRORS
The pthread_setspecific() function will fail if: ENOMEM Insufficient memory exists to associate the value with the key. The pthread_setspecific() function may fail if: EINVAL The key value is invalid. The pthread_getspecific() function does not return errors. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
pthread_key_create(3C), attributes(5), standards(5) SunOS 5.11 23 Mar 2005 pthread_getspecific(3C)
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