Set Scope

pthread_attr_setscope(3THR)

Use pthread_attr_setscope(3THR) to create a bound thread (PTHREAD_SCOPE_SYSTEM) or an unbound thread (PTHREAD_SCOPE_PROCESS).

Both thread types are accessible only within a given process.

Prototype:

int	pthread_attr_setscope(pthread_attr_t *tattr,int scope);

#include <pthread.h>

pthread_attr_t tattr;
int ret;

/* bound thread */
ret = pthread_attr_setscope(&tattr, PTHREAD_SCOPE_SYSTEM);

/* unbound thread */
ret = pthread_attr_setscope(&tattr, PTHREAD_SCOPE_PROCESS);

Notice that there are three function calls in this example: one to initialize the attributes, one to set any variations from the default attributes, and one to create the pthreads.

#include <pthread.h>

pthread_attr_t attr;
pthread_t tid;
void start_routine;
void arg;
int ret;

/* initialized with default attributes */
ret = pthread_attr_init (&tattr);

/* BOUND behavior */
ret =  pthread_attr_setscope(&tattr, PTHREAD_SCOPE_SYSTEM);
ret = pthread_create (&tid, &tattr, start_routine, arg);

Return Values

pthread_attr_setscope() returns zero after completing successfully. Any other return value indicates that an error occurred. If the following conditions occur, the function fails and returns the corresponding value.

EINVAL

An attempt was made to set tattr to a value that is not valid.