pthread_getattr_np(3) [netbsd man page]

PTHREAD_ATTR_GET_NP(3)					   BSD Library Functions Manual 				    PTHREAD_ATTR_GET_NP(3)

NAME

     pthread_attr_get_np -- get attributes of existing thread

LIBRARY

     POSIX Threads Library (libpthread, -lpthread)

SYNOPSIS

     #include <pthread.h>

     int
     pthread_attr_get_np(pthread_t thread, pthread_attr_t *attr);

     int
     pthread_getattr_np(pthread_t thread, pthread_attr_t *attr);

DESCRIPTION

     The pthread_attr_get_np() and pthread_getattr_np() functions can be used to retrieve attributes of a running thread.  The result is stored to
     attr.

     For pthread_attr_get_np() attr should be initialized prior to the call by using pthread_attr_init(3).  pthread_getattr_np() does this auto-
     matically.

     For both functions attr should be freed when it is not in use anymore with pthread_attr_destroy(3).

     Most fields of attr are the same ones provided during thread creation time as a parameter to pthread_create(3).  The exceptions include:

	   o   The detach state -- a joinable thread may have detached itself after the creation.

	   o   The guard size, which may vary if the application has allocated its own thread stack.

	   o   The stack address and size; pthread_attr_get_np() will always return the thread's real stack address and size, regardless of the
	       values in the original attributes structure.

     The returned pthread_attr_t structure is supposed to be used in conjunction with the pthread_attr_get*() functions to retrieve individual
     values from the structure.  When the returned attr is no longer needed, it should be destroyed by using pthread_attr_destroy(3).

RETURN VALUES

     Upon successful completion, pthread_attr_get_np() and pthread_getattr_np() return 0.  Otherwise an error number is returned to indicate the
     error.

COMPATIBILITY

     The pthread_attr_get_np() and pthread_getattr_np() functions are non-standard extensions.

ERRORS

     The pthread_attr_get_np() and pthread_getattr_np() functions will fail if:

     [ENOMEM]		Insufficient memory.

     [ESRCH]		Non-existent thread.

SEE ALSO

     pthread(3), pthread_attr(3)

BSD
								  August 6, 2010							       BSD

PTHREAD_ATTR(3) 					   BSD Library Functions Manual 					   PTHREAD_ATTR(3)

NAME

     pthread_attr_init, pthread_attr_destroy -- thread attribute operations

LIBRARY

     POSIX Threads Library (libpthread, -lpthread)

SYNOPSIS

     #include <pthread.h>

     int
     pthread_attr_init(pthread_attr_t *attr);

     int
     pthread_attr_destroy(pthread_attr_t *attr);

DESCRIPTION

     Thread attributes are used to specify parameters to pthread_create().  One attribute object can be used in multiple calls to
     pthread_create(), with or without modifications between the calls.  The pthread_attr_t type is an opaque representation of the thread
     attributes; any access to the object other than via the described pthread_attr_*() functions may result in undefined behavior.

     The pthread_attr_init() function initializes attr with the default thread attributes used in the implementation.  Depending on the implemen-
     tation, undefined behavior may follow if an uninitialized thread attribute object is used with some of the thread attribute functions.  It is
     therefore a good practice to always use pthread_attr_init(), even if this might be unnecessary.  Undefined behavior may also follow if an
     already initialized attr is used with pthread_attr_init().

     When the attribute object is no longer needed, it should be destroyed by using pthread_attr_destroy().  The function has no effect on threads
     that were created by using a given attribute object.  A destroyed attr can be reinitialized using pthread_attr_init(), but all other actions
     with the destroyed object are unspecified.

     The following standard thread attribute functions are available:

	   Function			    Description
	   pthread_attr_getdetachstate(3)   thread detach state
	   pthread_attr_getguardsize(3)     thread guard size
	   pthread_attr_getinheritsched(3)  inherit scheduler attribute
	   pthread_attr_getschedparam(3)    thread scheduling parameter
	   pthread_attr_getschedpolicy(3)   thread scheduling policy
	   pthread_attr_getscope(3)	    thread contention scope
	   pthread_attr_getstack(3)	    thread stack
	   pthread_attr_getstacksize(3)     thread stack size
	   pthread_attr_getstackaddr(3)     thread stack address

     Each listed pthread_attr_get*() function contains a pthread_attr_set*() counterpart.  In addition, the following NetBSD specific extensions
     are available:

	   Function			    Description
	   pthread_attr_get_np(3)	    attributes of a running thread
	   pthread_attr_getname_np(3)	    descriptive name of an attribute

RETURN VALUES

     If successful, these functions return 0.  Otherwise, an error number is returned to indicate the error.

ERRORS

     No errors are defined for pthread_attr_init() and pthread_attr_destroy().

SEE ALSO

     pthread_create(3), pthread_join(3)

STANDARDS

     Both pthread_attr_init() and pthread_attr_destroy() conform to IEEE Std 1003.1-2001 (``POSIX.1'').

BSD
								   July 9, 2010 							       BSD