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Questions tagged [pty]

A pty is a pseudo-terminal - it's a software implementation that appears to the attached program like a terminal, but instead of communicating directly with a "real" terminal, it transfers the input and output to another program.

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Confused about Docker -t option to Allocate a pseudo-TTY

What exactly does this option do? I've been reading a lot on TTY and I'm still confused. I played around without having the -t and just -i and it seems like programs that expect user input throw an error without the -t. Why is it important for…
user1099123
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How to fix request failed on channel 0

When I want to connect to my server like this ssh -a username@my-server.de -p 22 it gives me two error messages: PTY allocation request failed on channel 0 shell request failed on channel 0 When I use the parameter -T the first error message goes…
user1895268
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Can you fool isatty AND log stdout and stderr separately?

Problem So you want to log the stdout and stderr (separately) of a process or subprocess, without the output being different from what you'd see in the terminal if you weren't logging anything. Seems pretty simple no? Well unfortunately, it appears…
J.J
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How do I read the output of a child process without blocking in Rust?

I'm making a small ncurses application in Rust that needs to communicate with a child process. I already have a prototype written in Common Lisp. I'm trying to rewrite it because CL uses a huge amount of memory for such a small tool. I'm having some…
jkiiski
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Final output on slave pty is lost if it was not closed in parent. Why?

I wrote and maintain a program rlwrap that uses a pseudo-terminal to communicate with a child process. Pseudo-terminals (ptys) are found in all Unix(-like) systems, but they behave slightly differently on different platforms. Case in point: In…
Hans Lub
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Detecting when a child process is waiting for input

I'm writing a Python program for running user-uploaded arbitrary (and thus, at the worst case, unsafe, erroneous and crashing) code on a Linux server. The security questions aside, my objective is to determine, if the code (that might be in any…
miikkas
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Why use -T with ssh

To test ssh I read you need to use something like ssh -T user@domain.com: According to man ssh: -T Disable pseudo-terminal allocation. -t Force pseudo-terminal allocation. This can be used to execute arbitrary screen-based programs on…
Snowcrash
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Piping data to Linux program which expects a TTY (terminal)

I have a program in Linux which refuses to run if its stdin/stdout is not a TTY (terminal device). Is there an easy-to-use tool which will create a PTY, start the program with the newly created TTY, and copy all data over stdin/stdout? The use case…
pts
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Run command and get its stdout, stderr separately in near real time like in a terminal

I am trying to find a way in Python to run other programs in such a way that: The stdout and stderr of the program being run can be logged separately. The stdout and stderr of the program being run can be viewed in near-real time, such that if the…
J.J
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Why does running a background task over ssh fail if a pseudo-tty is allocated?

I've recently run into some slightly odd behaviour when running commands over ssh. I would be interested to hear any explanations for the behaviour below. Running ssh localhost 'touch foobar &' creates a file called foobar as expected: [bob@server…
Floating Octothorpe
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node-gyp error while doing npm install

I am doing npm install from a project and I am getting this wierd error in node-gyp. > pty.js@0.2.3 install /home/charizard/Open/terminal-codelearn/node_modules/pty.js > node-gyp rebuild npm http GET https://registry.npmjs.org/commander npm http…
Charizard_
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Connection to the terminal's pty host process is unresponsive

After installing VSCode, I started receiving this certain notification saying The connection to the terminal's pty host process is unresponsive, the terminals may stop working. The notification won't disappear until I click the restart button.…
AstrooKai.
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difference between pty and a pipe

I have been reading about ptys from this page's example: http://www.rkoucha.fr/tech_corner/pty_pdip.html. I have two questions: What is the difference, or the most important difference, between using a pty and using a pipe? From what I have read,…
kprincipe
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How to use pseudo-terminals in Linux with C?

I'm trying to figure out how to use pseudo-terminal's in linux, essentially I want to create a telnetd clone, something I mentioned in an earlier question. I understand the concept of master and slave terminal, and I have a basic grasp on how to use…
Irresponsible Newb
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Python: when to use pty.fork() versus os.fork()

I'm uncertain whether to use pty.fork() or os.fork() when spawning external background processes from my app. (Such as chess engines) I want the spawned processes to die if the parent is killed, as with spawning apps in a terminal. What are the ups…
Thomas Ahle
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