update libc-test/src/functional/pthread_gettid.c.

增加了互斥锁

libc-test/src/functional/pthread_gettid.c

@@ -2,27 +2,38 @@
 #include <string.h>
 #include "test.h"
 #include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
 
 #define TEST(c) ((c) ? 1 : (t_error(#c" failed: %s \n" ,strerror(errno)),0))
 
+static pthread_mutex_t mutex ;
+
 void* pthread_test(void* arg)
 {
     *((pid_t *)arg) = getpid();
+    pthread_mutex_lock(&mutex);
+    pthread_mutex_unlock(&mutex);
     return NULL;
 }
 
 int main(int argc, char const *argv[])
 {
+    pthread_mutex_init(&mutex, NULL);
+
+    TEST(getpid() == pthread_gettid(pthread_self()));//用通过主线程id获取的进程id与用getpid()获取的进程id比较
+
+    pthread_mutex_lock(&mutex);
     pid_t pid;
     pthread_t t;
     pthread_create(&t,NULL,pthread_test,&pid);//创建线程
 
-    TEST(getpid() == pthread_gettid(pthread_self()));//用通过主线程id获取的进程id与用getpid()获取的进程id比较
-
     pid_t recv_result = pthread_gettid(t);//利用线程id获取的进程id
 
     TEST(0 == pthread_join(t,NULL));//结合线程并且将退出的线程在链表中删除
 
+    pthread_mutex_unlock(&mutex);
+
     TEST(pid == recv_result);//将线程中获取的进程id与通过用线程id获取的进程id进行比较
 
     return 0;