How to execute a command inside a screen session

Question

I would like to know how to execute a command inside a screen session. i searched and I found this :

screen -S nameofscreen -X stuff "command"

When I type this, the command is typed inside the screen but it is not executed. So my queston is how to press enter using this command.

Answer 1

In the bash shell you can use ctrl-V to explicitly put non-printable characters into a string. So try ctrl-V ctrl-L ctrl-V ctrl-M at the end of your command just before the ".

Answer 2

I'd do something like this:

screen -S sessionName bash -c 'cmd; exec bash'

it starts a new session executes cmd and launches shell (otherwise it'd drop that new session).

-X will allow you to send input to a specified session -- that's why your command didn't execute. To execute it you'd need to add enter sign like Paul suggested. It can be done with Ctrl+v and then Enter. That will produce that ^M. So:

screen -S sessionName -X stuff 'cmd^M'

That, in itself, won't however attach a detached session.

Answer 3

In bash, you can use \n in the $'...' construct:

screen -S nameofscreen -X stuff $'command\n'

Answer 4

It took me some time, but what I found is: Version of screen 4.06 has a bug. If you want to send a command over a shared screen session like this, it fails:

screen -S shared_session_name -X stuff "command \n"

Screen fails with an error:

Cannot opendir /run/screen/S-$USER: Permissions denied

After update to the version screen 4.09 it works.