sleep

The 'sleep' function suspends the execution of the current thread for a specified interval.
'sleep'函数让当前进程暂停

• Prototype: sleep(nMilliSeconds);
• Parameters:
  1. nMilliSeconds, specifies a sleep time in milliseconds.
     指定的暂停时间，单位为millisecond
• Return Value: None.
• Example:

  sleep(1000);