在日常使用linux时，有时候需要将标准输入的内容从定向文件，但是同时又想在屏幕上显示看到内容。这是我们可以使用tee命令。tee命令读取标准输入中的内容，把这些内容同时输出到指定的多个文件或标准输出，。 tee命令可以重定向标准输入到多个不同的文件中，
options
-a,--append，将标准输入的内容追加到目标文件，而不是覆盖 -i，--ignore-interrupts，忽略中断信号 演示： 1、使用tee命令将标准输入输出到多个文件 [root@mgr1 ~]# tee a b aaa aaa ^C [root@mgr1 ~]# more a aaa [root@mgr1 ~]# more b aaa 2、将内容同时输出到屏幕和文件 [root@mgr1 ~]# tcpdump -i ens33 -nnA "port 9200"|tee a tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on ens33, link-type EN10MB (Ethernet), capture size 262144 bytes 16:11:50.826610 IP 10.0.2.1.61596 > 10.0.2.3.9200: Flags [S], seq 2340118445, win 64240, options [mss 1460,nop,wscale 8,nop,nop,sackOK] , length 0E..42.@.@..? ... .....#..{_.........\f.............. 16:11:50.826731 IP 10.0.2.3.9200 > 10.0.2.1.61596: Flags [S.], seq 3515684317, ack 2340118446, win 29200, options [mss 1460,nop,nop,sac kOK,nop,wscale 7], length 0E..4..@.@.". ... ...#........{_...r..*.............. 16:11:50.826868 IP 10.0.2.1.61597 > 10.0.2.3.9200: Flags [S], seq 2648642735, win 64240, options [mss 1460,nop,wscale 8,nop,nop,sackOK] , length 0E..42.@.@..> ... .....#............................. 16:11:50.826902 IP 10.0.2.3.9200 > 10.0.2.1.61597: Flags [S.], seq 3477066367, ack 2648642736, win 29200, options [mss 1460,nop,nop,sac kOK,nop,wscale 7], length 0E..4..@.@.". [root@mgr1 ~]# more a 16:11:50.826610 IP 10.0.2.1.61596 > 10.0.2.3.9200: Flags [S], seq 2340118445, win 64240, options [mss 1460,nop,wscale 8,nop,nop,sackOK] , length 0 E..42.@.@..? ... .....#..{_.........\f.............. 16:11:50.826731 IP 10.0.2.3.9200 > 10.0.2.1.61596: Flags [S.], seq 3515684317, ack 2340118446, win 29200, options [mss 1460,nop,nop,sac kOK,nop,wscale 7], length 0 E..4..@.@.". ... ...#........{_...r..*.............. 16:11:50.826868 IP 10.0.2.1.61597 > 10.0.2.3.9200: Flags [S], seq 2648642735, win 64240, options [mss 1460,nop,wscale 8,nop,nop,sackOK] , length 0 E..42.@.@..> ... .....#............................. 16:11:50.826902 IP 10.0.2.3.9200 > 10.0.2.1.61597: Flags [S.], seq 3477066367, ack 2648642736, win 29200, options [mss 1460,nop,nop,sac kOK,nop,wscale 7], length 0 E..4..@.@.". ... ...#....?........r..*.............. 16:11:50.826983 IP 10.0.2.1.61596 > 10.0.2.3.9200: Flags [.], ack 1, win 4106, length 0 E..(2.@.@..I