The screen command usages and examples – Unix/Linux

The screen command under the Unix is used to execute processes inside a screen session.

That means you can simply detach from the screen and keep working on that server. It is normally very helpful when you need to install some time consuming applications on the server.

In this case, you can execute that installation on a screen. The process still runs on that screen, even if you got connection dropped. After sometime you can re-attach that screen and control that process.

Here, I am explaining some common screen command usages and examples:

The command “screen“;

The command “screen” simply open a screen window for your process. You can execute the command over there and can detach the screen safely.

Usage

screen

Use Ctrl + AD(press CTRL+A followed by d) to detach from screen.

Or, you may open the screen with your process itself.
Example:

screen top

In this example, the top command will execute under the screen [Screen0].

Other important switches

To view the screen;

screen -x

Example:

[root@vps ~]# screen -x
There are several suitable screens on:
        5270.one        (Detached)
        5281.two     (Detached)
Type "screen [-d] -r [pid.]tty.host" to resume one of them.

Usage:

[root@vps ~]# screen -x 5270.one

List all screens;

screen -ls

Example:

[root@vps ~]# screen -ls
There are screens on:
        5270.one        (Detached)
        5281.two     (Detached)
2 Sockets in /var/run/screen/S-root.

To attach to a running session;

screen -r

Example

[root@vps ~]# screen -r 5270.one 

How to rename the screen session? Is there any way to rename the screen session name?

Yep, we can change the name by using the “-X” switch with “sessionname” parameter.

Syntax

screen -S current.session -X sessionname new.name

Example

I’ve two running session “one” and “two” and I want to change the session name “two” to “backup”. Here is the command to do so:

[root@vps ~]# screen -ls
There are screens on:
        5270.one        (Detached)
        5281.two        (Detached)
2 Sockets in /var/run/screen/S-root.

# screen -S 5281.two -X sessionname backup

Now see the names;

[root@vps ~]# screen -ls
There are screens on:
        5270.one        (Detached)
        5281.backup     (Detached)
2 Sockets in /var/run/screen/S-root.

That’s it!

Related:
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