gettid()获取线程ID测试程序

1、第一种方法

#include "stdio.h"
#include "stdlib.h"
#include "unistd.h"
#include "pthread.h"
#include <sys/syscall.h>
#define gettid() syscall(__NR_gettid)
const int M = 3;
pthread_t hThread[M];
int threadId[M];
void *hello(void *ptr) {
	int id = *(int *)(ptr);
	printf("Hello! %d/n", id);
	printf("Thread id:%d/n", gettid());
	sleep(1);
	
}
void initThreade() {
	int i;
	for (i = 0; i < M; ++i) {
		threadId[i] = i;
	}
}
void MyThreads() {
	int i;
	for (i = 0; i < M; i++) {
		pthread_create(hThread + i, NULL, hello, (void *)(threadId + i));
	}
	for (i = 0; i < M; i++) {
		pthread_join(hThread[i], NULL);
	}
}
int main(){
	initThreade();
	MyThreads();
	return 0;
}

g++ hello.c -o hello -lpthread

[root@zhuliting ft]# g++ hello.c -o hello -lpthread

[root@zhuliting ft]# ./hello

Hello! 0

Thread id:17783

Hello! 1

Thread id:17784

Hello! 2

Thread id:17785





注意：

1、第5、6行不能少，否则会出现错误：error: ‘gettid’ was not declared in this scope

2、#include
<sys/types.h>代替第5、6行

http://www.kernel.org/doc/man-pages/online/pages/man2/gettid.2.html

3、编译加上-lpthread选项，不然会出现“undefined reference to `pthread_create'”错误