Name | Synopsis | Description | Return Values | Errors | Attributes | See Also
cc –mt [ flag... ] file... –lpthread [ library... ] #include <pthread.h> int pthread_attr_init(pthread_attr_t *attr);
int pthread_attr_destroy(pthread_attr_t *attr);
The function pthread_attr_init() initializes a thread attributes object attr with the default value for all of the individual attributes used by a given implementation.
The resulting attribute object (possibly modified by setting individual attribute values), when used by pthread_create(), defines the attributes of the thread created. A single attributes object can be used in multiple simultaneous calls to pthread_create().
The pthread_attr_init() function initializes a thread attributes object ( attr) with the default value for each attribute as follows:
Attribute |
Default Value |
Meaning of Default |
---|---|---|
contentionscope |
PTHREAD_SCOPE_PROCESS |
resource competition within process |
detachstate |
PTHREAD_CREATE_JOINABLE |
joinable by other threads |
stackaddr |
NULL |
stack allocated by system |
stacksize |
NULL |
1 or 2 megabyte |
priority |
0 |
priority of the thread |
policy |
SCHED_OTHER |
determined by system |
inheritsched |
PTHREAD_EXPLICIT_SCHED |
scheduling policy and parameters not inherited but explicitly defined by the attribute object |
guardsize |
PAGESIZE |
size of guard area for a thread's created stack |
The pthread_attr_destroy() function destroys a thread attributes object ( attr), which cannot be reused until it is reinitialized. An implementation may cause pthread_attr_destroy() to set attr to an implementation-dependent invalid value. The behavior of using the attribute after it has been destroyed is undefined.
Upon successful completion, pthread_attr_init() and pthread_attr_destroy() return a value of 0. Otherwise, an error number is returned to indicate the error.
The pthread_attr_init() function will fail if:
Insufficient memory exists to initialize the thread attributes object.
The pthread_attr_destroy() function may fail if:
attr is invalid.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE |
ATTRIBUTE VALUE |
---|---|
Interface Stability |
Standard |
MT-Level |
MT-Safe |
sysconf(3C), pthread_attr_getdetachstate(3C), pthread_attr_getguardsize(3C), pthread_attr_getinheritsched(3C), pthread_attr_getschedparam(3C), pthread_attr_getschedpolicy(3C), pthread_attr_getscope(3C), pthread_attr_getstackaddr(3C), pthread_attr_getstacksize(3C), pthread_attr_setdetachstate(3C), pthread_attr_setguardsize(3C), pthread_attr_setinheritsched(3C), pthread_attr_setschedparam(3C), pthread_attr_setschedpolicy(3C), pthread_attr_setscope(3C), pthread_attr_setstackaddr(3C), pthread_attr_setstacksize(3C), pthread_create(3C), attributes(5), standards(5)
Name | Synopsis | Description | Return Values | Errors | Attributes | See Also