history命令

history命令可以显示之前输入过的所有命令，按时间顺序编号，如果要执行之前的命令，使用!n就可以了，其中n为要执行的命令的编号。
linux-suse:~ # history
    1  ifconfig
    2  ls
    3  chmod 777 jrockit-R27.5.0-jdk1.6.0_03-linux-x64.bin
    4  ./jrockit-R27.5.0-jdk1.6.0_03-linux-x64.bin
    5  ls
    6  makedir specpower
    7  mkdir specpower

linux-suse:~ # !1
ifconfig
eth0      Link encap:Ethernet  HWaddr 00:04:23:C7:17:A2
          inet addr:172.18.1.202  Bcast:172.18.1.255  Mask:255.255.255.0
          inet6 addr: fe80::204:23ff:fec7:17a2/64 Scope:Link
          UP BROADCAST NOTRAILERS RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:263475 errors:0 dropped:0 overruns:0 frame:0
          TX packets:96903 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:267151638 (254.7 Mb)  TX bytes:7858935 (7.4 Mb)
          Base address:0xdc00 Memory:fcfa0000-fcfc0000