Questions tagged [pts]

20 questions
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What is `/dev/console` used for?

From this answer to Linux: Difference between /dev/console , /dev/tty and /dev/tty0 From the documentation: /dev/tty Current TTY device /dev/console System console /dev/tty0 Current virtual console In the good old days /dev/console was…
Tim
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1 answer

read(2) blocking behaviour changes when pts is closed resulting in read() returning error: -1 (EIO)

I'm trying to figure out how I can reliably loop a read on a pt master I have. I open the ptmx, grant and unlock it as per usual: * ptmx stuff */ /* get the master (ptmx) */ int32_t masterfd = open("/dev/ptmx", O_RDWR | O_NOCTTY); if(masterfd < 0){ …
Supernovah
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w command doesn't show all pseudo-terminal sessions

If I open terminal and execute w command then it will show: user tty7 :0 12:04 39:56 36.87s 0.06s /sbin/upstart - Now if open terminator or xterm and execute w command then it will show it's entry in the output of w command…
Prvt_Yadav
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identify process sending a signal to a shell script

I've written a shell script that uses the trap feature to output its progress when it receives a SIGUSR1 signal, but I don't see how to have the script be able to output the progress to the STDOUT of the process which sent the signal. So, if the…
user1404316
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Associating pts and tty to a process

I am trying to find out which tty or pts is being run by which process. My research so far is that: tty is a kernel or backend terminal to handle lower level stuffs pts is a pesudo terminal to allow user to communicate with the system there are a…
user357066
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How can we find out the pseudoterminal master and slave from each other?

A pseudoterminal has a pair of master and slave. How can we find out the master device file from a slave device file (e.g. /etc/pts/3)? I only find /dev/ptmx and /dev/pts/ptmx, but they can't be shared by multiple slaves. Given one of the processes…
Tim
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Is this output from “who -a” normal?

This does not look normal to me: who -a system boot 2018-09-04 11:59 LOGIN tty1 2018-09-04 11:59 685 id=tty1 run-level 5 2018-09-04 11:59 user + pts/0 2018-09-04 20:39 . 19612…
somethingSomething
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Why dmesg output displayed on /dev/tty1

This is still related to my yesterday thread, so there's alert or maybe it's just log that displayed on my terminal on /dev/tty1. Ofcourse it's annoying because it's displayed in my bash prompt, so whenever I want input something, my input has been…
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ssh pseudoterminal special character problems

So I have the following situation: I have a host that exhibits unexpected behavior when using ssh -t combined with tmux. If I call ssh -t my-problem-host tmux non-ascii characters (e.g. €) are displayed as _. If I connect without calling tmux, there…
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Is `/dev/tty7` not directly accessible to Ubuntu users?

On Ubuntu, /dev/tty7 is the virtual console for desktop GUI. Is the only way to access /dev/tty7 to use chvt 7 or Ctrl+Alt+F7? Besides that, is /dev/tty7 not directly accessible to Ubuntu users, but indirectly via other emulations of terminals…
Tim
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documentation on ptmx and pts

I am want to stream a linux terminal to my own program, and as far as I understand this is done by opening /dev/ptmx to start a new pts, I have tested this and this does indeed work (it creates a new file in /dev/pts). But I am not sure how I am…
TT-392
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How to restrict a user from using tty?

i was wondering if it is possible to force log out a user (anyone other than root) when trying to login via tty (ctrl+tab+f1/f2/f3..). The user should be able to use pts with no problems. Using CentOS 7.
Harish Agadi
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How to remove sshd pts processes in status D without restarting servers

Why are these sshd-pts processes stuck in status D? It seems the system load averages are increasing due to these processes. How can I remove them without restarting my server. (add ppid and etime) [root@manager ~]# ps -eo…
Wenyi Li
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1 answer

Restore default permissions on /dev/pts

Hey guys I tried to activate multiuser for some screens so I used screen -A -m -d -S test screen -S stest -X multiuser on screen -S test -X acladd testuser But I got chmod /dev/pts/17: Permission denied Unfortunately I thought it would be a great…
Markus
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screen /dev/pts/ of a VM never has correct stty settings

A virtual machine (using linux+kvm+qemu) is setup to provided a serial port for a terminal, which is made available via a pseudo-terminal, some random /dev/pts/ I use screen as a way to interact with /dev/pts/, as it has proven…
fraleone
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