Linux 下screen命令的使用

刚刚才注意，默认情况下rhel6 是不安装screen命令的：

[root@rhel63single yum.repos.d]# yum install screen
Loaded plugins: product-id, refresh-packagekit, security, subscription-manager
Updating certificate-based repositories.
Unable to read consumer identity
rhel-source                                                                                                                          | 4.0 kB     00:00 ... 
rhel-source-beta                                                                                                                     | 4.0 kB     00:00 ... 
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package screen.x86_64 0:4.0.3-16.el6 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

============================================================================================================================================================
 Package                           Arch                              Version                                   Repository                              Size
============================================================================================================================================================
Installing:
 screen                            x86_64                            4.0.3-16.el6                              rhel-source                            494 k

Transaction Summary
============================================================================================================================================================
Install       1 Package(s)

Total download size: 494 k
Installed size: 795 k
Is this ok [y/N]: y
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing : screen-4.0.3-16.el6.x86_64                                                                                                                          1/1 
Installed products updated.
  Verifying  : screen-4.0.3-16.el6.x86_64                                                                                                                          1/1 

Installed:
  screen.x86_64 0:4.0.3-16.el6                                                                                                                                         

Complete!
[root@rhel63single yum.repos.d]# which screen
/usr/bin/screen
[root@rhel63single yum.repos.d]# 

一、screen 的建立

[root@rhel63single ~]# screen -ls
No Sockets found in /var/run/screen/S-root.

[root@rhel63single ~]# 
[root@rhel63single ~]# 
[root@rhel63single ~]# screen -dmS lei1
[root@rhel63single ~]# screen -ls
There is a screen on:
        5786.lei1       (Detached)
1 Socket in /var/run/screen/S-root.

[root@rhel63single ~]#
其中：5786是linux的ospid。lei1是会话的名称。

二、screen 的进入

[root@rhel63single ~]# screen -r lei1

三、暂时退出某个screen 的session ：先按ctrl ，再按小写的a，再按小写的d

[root@rhel63single ~]# 


            
[detached]
[root@rhel63single ~]# 

四、若是本来就在该session中，再使用screen -r lei1命令时的提示：

[root@rhel63single ~]# screen -r lei  或者用screen -r 5786
There is a screen on:
        5786.lei1       (Attached)
There is no screen to be resumed matching lei.
[root@rhel63single ~]# 

五、状态解释：

[root@rhel63single ~]# screen -dmS lei2
[root@rhel63single ~]# 
[root@rhel63single ~]# 
[root@rhel63single ~]# 
[root@rhel63single ~]# screen -ls
There are screens on:
        5850.lei2       (Detached)---->挂起状态，无终端在连接会话
        5786.lei1       (Attached)---->有终端在连接会话。
2 Sockets in /var/run/screen/S-root.

[root@rhel63single ~]# 

六、永久退出screen中的本session

[root@rhel63single ~]# exit
                           exit


                        
[screen is terminating]
[root@rhel63single ~]# screen -ls
There is a screen on:
        5850.lei2       (Detached)
1 Socket in /var/run/screen/S-root.

 

七、检查screen中的其他session的来源ip：

[root@rhel63single ~]# who -a
           system boot  2015-03-19 12:36
           run-level 5  2015-03-19 12:36
LOGIN      tty2         2015-03-19 12:37              1979 id=2
LOGIN      tty4         2015-03-19 12:37              1983 id=4
LOGIN      tty3         2015-03-19 12:37              1981 id=3
LOGIN      tty5         2015-03-19 12:37              1985 id=5
LOGIN      tty6         2015-03-19 12:37              1987 id=6
root     + pts/0        2015-03-19 19:05 00:17        5306 (192.168.80.1)
           pts/1        2015-03-19 22:29              5787 id=/1    term=0 exit=0
           pts/2        2015-03-19 22:33              5810 id=ts/2  term=0 exit=0
root     + pts/3        2015-03-19 22:33   .          5830 (192.168.80.1)
root     + pts/4        2015-03-19 22:42 00:11        5851 (192.168.80.1:S.0)---->注意此处
[root@rhel63single ~]# screen -ls
There is a screen on:
        5850.lei2       (Attached)
1 Socket in /var/run/screen/S-root.

[root@rhel63single ~]# ps -ef | grep 5851---->注意此处
root      5851  5850  0 22:33 pts/4    00:00:00 /bin/bash
root      5974  5830  0 22:56 pts/3    00:00:00 grep 5851
[root@rhel63single ~]# ps -ef | grep 5850---->注意此处
root      5850     1  0 22:33 ?        00:00:00 SCREEN -dmS lei2 ---->注意此处
root      5851  5850  0 22:33 pts/4    00:00:00 /bin/bash ---->注意此处
root      5883  5810  0 22:42 pts/2    00:00:00 screen -r 5850
[root@rhel63single ~]# 

八、检查当前的提示符是否处于screen的session中：

按ctrl，再按a,再按t

此时，在左下角会显示：“22:45:06 Mar 19 rhel63single 0.00 0.00 0.00” 字样
格式为：当前时间，日期，主机名，负载情况

九、杀掉screen中的其他session

[root@rhel63single ~]# kill -9 5850
[root@rhel63single ~]# screen -ls
There is a screen on:
        5850.lei2       (Dead ???)
Remove dead screens with 'screen -wipe'.
1 Socket in /var/run/screen/S-root.

[root@rhel63single ~]# screen -wipe
There is a screen on:
        5850.lei2       (Removed)
1 socket wiped out.
No Sockets found in /var/run/screen/S-root.

[root@rhel63single ~]# screen -ls
No Sockets found in /var/run/screen/S-root.

[root@rhel63single ~]# 

然后，被杀掉的session 有提示：

[root@rhel63single ~]# 
Suddenly the Dungeon collapses!! - You die...
[root@rhel63single ~]#