"screen is terminating" for non-root

Question

When I try to run screen as a non-root user I get:

screen

[screen is terminating]

immediately, though it works fine for root

ls -alh /usr/bin/screen
-rwxr-sr-x 1 root screen 465K Jun  9 20:30 /usr/bin/screen

When googling around I noticed a mention of /etc/fstab, here is mine:

# <file system> <mount point>   <type>  <options>       <dump>  <pass>
/dev/md1        /       ext4    errors=remount-ro       0       1
/dev/md2        /home   ext4    defaults        1       2
/dev/sda3       swap    swap    defaults        0       0
/dev/sdb3       swap    swap    defaults        0       0
proc            /proc   proc    defaults                0       0
sysfs           /sys    sysfs   defaults                0       0
tmpfs           /dev/shm        tmpfs   defaults        0       0
devpts          /dev/pts        devpts  defaults        0       0

This on a freshly installed centos 7 on a dedicated server accessed through ssh ( TTY is pts )

Any help would be appreciated.

screen -ls    
No Sockets found in /var/run/screen/S-user.

ls -la /var/run/screen/S-user
total 0
drwx------ 2 user user 40 Jul 10 18:23 .
drwxrwxr-t 4 root     screen   80 Jul 10 17:59 ..

Run screen -ls; it should give a directory name in the first line. Then, run ls -la <above directory name> and put the output in your question. — BenjiWiebe, Jul 11 '14 at 02:11
Hmmmm...I expected to see a permissions problem there, but it looks fine. — BenjiWiebe, Jul 11 '14 at 03:32
I am trying to get a VM of CentOS 7 going to see if it also has this problem, but I might not get it done til tomorrow... — BenjiWiebe, Jul 11 '14 at 03:37
Is there a reason you need CentOS 7? It seems that perhaps it is related to the fact that CentOS 7 was just released. Perhaps you could use CentOS 6 for a few more weeks? — BenjiWiebe, Jul 11 '14 at 19:32
I do not have the same problem on a fresh install of CentOS 7. — BenjiWiebe, Jul 11 '14 at 19:32

score 16 · Answer 1 · edited Dec 03 '14 at 00:02

16

I had this issue on Dedicated CentOS 7 server, and came across the fix described in this bug report: bugs.centos.org/view.php?id=7395

That was a fine solution on the Dedicated to add gid=5 to devpts in fstab. screen now works as expected for all users.

However, I ran across this thread as I was trying to solve the issue on an OpenVZ container of CentOS 7. As there isn't a way to edit the fstab for the server (as far as I could find), I found the following work-around fixed it.

I figured I would drop back by this way and see if it might help anyone else out. (Albeit isn't a very pretty way of doing it.)

In terminal:

chmod u+s /usr/bin/screen
chmod 755 /var/run/screen

edited Dec 03 '14 at 00:02

Sun

6,318

answered Dec 02 '14 at 22:52

Csnap

260

This answer solved the issue for me, Ubuntu 18.04 running on openvz container – aafirvida Dec 27 '18 at 22:49
As the mentioned link doesn't work anymore (neither the one in the Wayback machine or the original one), I'm afraid I don't fully understand the answer. However, I made the chmod permission changes, added my user to the screen group, and it works again. – Tobias Oct 04 '23 at 13:20
FYI: The solution at the link was to add the parameter gid=5 into the devpts line in the server's /etc/fstab. OpenVZ containers don't allow you to make this modification, so I was prefacing my answer with that information to help make the distinction in solutions. – Csnap Oct 11 '23 at 14:14

score 5 · Answer 2 · answered May 27 '17 at 06:28

Ensure no other screen is using that device

This can be achieved with How can I determine what process has a file open in Linux? :

sudo lsof /dev/ttyS0

And then kill that process if that is the case.

For some reason, under this condition, sudo screen can still access the device, but then that connection will miss characters, which are consumed by the other screen.

Ensure the user has read and write permission to the file

E.g. on Ubuntu you want to add the user to the dialout group: https://askubuntu.com/a/133244/52975

thanks for lsof, I didn't know that I already have two screens running in the background — Marecky, Dec 24 '17 at 00:02

score -3 · Answer 3 · answered Feb 13 '17 at 09:21

-3

It might be an errors in your config file

~/.screenrc

Try to check it or create dimmy one.

answered Feb 13 '17 at 09:21

Алексей Ч

1

1

This is really a comment and not an answer to the original question. You can always comment on your own posts, and once you have sufficient reputation you will be able to comment on any post. Please read Why do I need 50 reputation to comment? What can I do instead? – DavidPostill Feb 13 '17 at 10:04

"screen is terminating" for non-root

3 Answers3