How to call default thread creation using c programming

#include
pthread_attr_t tattr;
pthread_t tid;
extern void *start_routine(void *arg);
void *arg;
int ret;
/* default behavior*/
ret = pthread_create(&tid, NULL, start_routine, arg);

/* initialized with default attributes */
ret = pthread_attr_init(&tattr);
/* default behavior specified*/
ret = pthread_create(&tid, &tattr, start_routine, arg);

The pthread_create() function is called with attr having the necessary state behavior. start_routine is the function with which the new thread begins execution. When start_routine returns, the thread exits with the exit status set to the value returned by start_routine.

When pthread_create is successful, the ID of the thread created is stored in the location referred to as tid.



Creating a thread using a NULL attribute argument has the same effect as using a default attribute; both create a default thread. When tattr is initialized, it acquires the default behavior.

pthread_create() returns a zero and exits when it completes successfully. Any other returned value indicates that an error occurred.