This custom originated in military camps since ancient times. Because the sergeant is not allowed to make any noise at night when marching or camping, it is estimated that one is afraid of interfering with the sergeant on duty who is responsible for vigilance; Second, I am afraid that the "Xiao Tian Camp" (Xiao Tian Camp-Night Camp suddenly sends out sharp screams to attack nervous soldiers, causing confusion, leading to either the enemy taking the opportunity to raid; Or the phenomenon of sergeant mutiny) led to the accident. Therefore, the military regulations stipulate that you can't whistle, scream or fight at night.
In ancient times, people were superstitious and thought that "Xiao Tian Ying" was the work of ghosts who died in battle. So as soon as it was extended, there was a saying that whistling at night would attract ghosts.
There are many stories about Roaring Camp ... I won't list them here. The information that is easy to find is The Sword with Royal Blood written by Mr. Jin Yong, which explains in detail the roaring camp of the invading army led by Li Xin after Li Xin was given the title of King Chuang ... It seems to be mentioned in the appendix of The Sword with Royal Blood (original version).