__thread:在多線程變成中，使用于global變量，使每個線程都私有一份。 static __thread int count; void *function1(void *argc) { printf("porgran pid:%u, the function1 pthread id is %lu, count:%d\n",getpid(), pthread_self(), count); count = 10; printf("porgran pid:%u, last the function1 pthread id is %lu, count:%d\n",getpid(), pthread_self(), count);
return 0; } void *function2(void *argc) { printf("porgran pid:%u, the function2 pthread id is %lu, count:%d\n", getpid(), pthread_self(), count); sleep(2); count = 100; printf("porgran pid:%u, last the function2 pthread id is %lu, count:%d\n", getpid(), pthread_self(), count);
return 0; }
int main() { pthread_t ?thread_id[2]; int ret; pthread_t mian_thread_id; mian_thread_id = pthread_self(); count = 2; printf("porgran pid:%u, mian_thread_id:%lu, count:%d\n", getpid(), mian_thread_id, count);
ret = pthread_create(thread_id, NULL, function1, NULL); assert(ret == 0);
ret = pthread_create(thread_id + 1, NULL, function2, NULL); assert(ret == 0);
ret = pthread_join(thread_id[0], NULL); assert(ret == 0); ret = pthread_join(thread_id[1], NULL); assert(ret == 0);
count = 1000; printf("porgran pid:%u, last mian_thread_id:%lu, count:%d\n", getpid(), mian_thread_id, count); return 0; }
__typeof__(var) 是gcc對C語言的一個擴展保留字，用于聲明變量類型,var可以是數據類型（int， char*..),也可以是變量表達式。
define DEFINE_MY_TYPE(type, name) __thread __typeof__(type) my_var_##name
DEFINE_MY_TYPE(int, one); //It ? is ? equivalent ? to ?'__thread int ?my_var_'; which is a thread variable. int main() { __typeof__(int *) x; //It ? is ? equivalent ? to ?'int ?*x';
__typeof__(int) a;//It ? is ? equivalent ? to ?'int ?a';
__typeof__(*x) ?y;//It ? is ? equivalent ? to ?'int y';
__typeof__(&a) b;//It ? is ? equivalent ? to ?'int ?b';
__typeof__(__typeof__(int *)[4]) ? z; //It ? is ? equivalent ? to ?'int ?*z[4]'; y = *x; b = &a; z[0] = x; z[1] = &a; return 0; }

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