增加 pthread_create 和 pthread_join 函数.

Signed-off-by: rick.chan <chenyang@autoai.com>

Software/Development/OperatingSystem/Linux/User/API/Linux_常用_C_API.md

@@ -62,4 +62,74 @@ The usleep() function returns 0 on success. On error, -1 is returned, with errno
 
 ### 3.1.pthread_create 函数
 
+**头文件：**
+
+```cpp
+#include <pthread.h>
+```
+
+**连接库：**
+
+```Makefile
+-pthread
+```
+
+**函数原型：**
+
+```cpp
+int pthread_create(pthread_t *thread, const pthread_attr_t *attr, void *(*start_routine) (void *), void *arg);
+```
+
+**说明：**
+
+The pthread_create() function starts a new thread in the calling process.
+
+**参数：**
+
+thread：Before returning, a successful call to pthread_create() stores the ID of the new thread in the buffer pointed to by thread; this identifier is used to refer to the thread in subsequent calls to other pthreads functions.
+
+attr：The attr argument points to a pthread_attr_t structure whose contents are used at thread creation time to determine attributes for the new thread; this structure is initialized using pthread_attr_init(3) and related functions. If attr is NULL, then the thread is created with default attributes.
+
+start_routine：The new thread starts execution by invoking start_routine()
+
+arg：Is passed as the sole argument of start_routine().
+
+**返回值：**
+
+On success, pthread_create() returns 0; on error, it returns an error number, and the contents of *thread are undefined.
+
 ### 3.3.pthread_join 函数
+
+**头文件：**
+
+```cpp
+#include <pthread.h>
+```
+
+**连接库：**
+
+```Makefile
+-pthread
+```
+
+**函数原型：**
+
+```cpp
+int pthread_join(pthread_t thread, void **retval);
+```
+
+**说明：**
+
+The pthread_join() function waits for the thread specified by thread to terminate. If that thread has already terminated, then pthread_join() returns immediately. The thread specified by thread must be joinable.
+
+If multiple threads simultaneously try to join with the same thread, the results are undefined. If the thread calling pthread_join() is canceled, then the target thread will remain joinable (i.e., it will not be detached).
+
+**参数：**
+
+thread：The pthread_join() function waits for the thread specified by thread to terminate.
+
+retval：If  retval  is not NULL, then pthread_join() copies the exit status of the target thread (i.e., the value that the target thread supplied to pthread_exit(3)) into the location pointed to by retval. If the target thread was canceled, then PTHREAD_CANCELED is placed in the location pointed to by retval.
+
+**返回值：**
+
+On success, pthread_join() returns 0; on error, it returns an error number.