Sleep函数_百度百科
http://baike.baidu.com/link?url=EmOxsG_du8HdLbv_9nDVlahpZOQ6DgkoLKooQInorAqIl_CEhCvBzTC6ALfYfPtVI1G2X9G-LJAnGJJ0zyFEzK
Sleep (system call) - Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Sleep_(system_call)
Linux sleep函数_百度百科
http://baike.baidu.com/link?url=-XiKw_RdfGQY87k3Im6fitZEgrgKQnE2WquyYnsHXPnw3YV1hcaaZgPJUbbaBWye4aqELpSIGvnF1b3O7MGnGaOR2IHMIZdZW_MVCL-e0Fy
C examples
In Windows OS:
Sleep(2*1000); // Sleep for 2 seconds
In Unix:
sleep(2); // Sleep for 2 seconds