[bestcoder@localhost test1]$ history
    1  history
    2  history -a
    3  history 
    4  pwd
    5  date
    6  cat test1
    7  cd test1
    8  history

[bestcoder@localhost ~]$ history
    1  history

[bestcoder@localhost test1]$ !2
history -a
[bestcoder@localhost test1]$ !4
pwd
/home/bestcoder/test1
[bestcoder@localhost test1]$ !date
date
2015年 09月 09日 星期三 22:28:13 PDT