What do flags -i and -t mean in terms of docker run? [duplicate]

I am very new to Docker and also to Unix/Linux world. I have been using docker to build my images and spin up some containers and do understand the concept of containerization fairly well. However, sometimes I do see some people spinning up containers using flags like :

docker run -i -t imagename

I tried to understand the value of it and came across docker documentation here : https://docs.docker.com/v1.13/engine/reference/run/

and it has some very arcane explainations like

-i: Keep STDIN open even if not attached

-t: Allocate a pseudo-tty

what does it even mean?

1

Best Answer

https://docs.docker.com/engine/reference/run/#foreground

-a=[] : Attach to STDIN, STDOUT and/or STDERR
-t : Allocate a pseudo-tty
--sig-proxy=true: Proxy all received signals to the process (non-TTY mode only)
-i : Keep STDIN open even if not attached

If you do not specify -a then Docker will attach to both stdout and stderr . You can specify to which of the three standard streams (STDIN, STDOUT, STDERR) you’d like to connect instead, as in:

$ docker run -a stdin -a stdout -i -t ubuntu /bin/bash

For interactive processes (like a shell), you must use -i -t together in order to allocate a tty for the container process.
-i -t is often written -it as you’ll see in later examples.
Specifying -t is forbidden when the client is receiving its standard input from a pipe.

Random Posts

Notepadd++ plugin sqlinform for SQL formatting bright orange color backgroundsql split string by space into table in postgresqlUse String.contains in an Apex pageCannot get a QT "hello world" to work!Object type in mongooseNot able to connect to my local graphql server with apollo studio sandboxLinux/Unix check if VPN connection is Active/UpHow do I use generate_series() in SQL in the middle of a string?What does typing.cast do in Python?Max retries exceeded with URL in requestsCreate certificate with QCStatements using OpenSSLcan not find the spring boot plugin in intellij ideaUnable to install phpMyAdmin on CentOS 7How do you or a vector with a single bit in verilog?Do I need to run the custom docker image in bitbucket pipelines?Google Apps Script - IF ELSE with multiple conditions combined with AND and ORsonarqube scanner on circleciInmon data Marts vs Kimball data martsHow to set up Pinia getter in Vue 3 Composition APIWhat is Folding technique in hashing and how to implement it?