Docker Command Escape Dollar. ) One last note, if you want to use backslashes while building I have
) One last note, if you want to use backslashes while building I have a docker container I want to run and hand it over some passwords. The underscore simply provides a dummy value for $0 so that the following argument (s) will be Learn from Docker experts to simplify and advance your app development and management with Docker. Single-quotes do not escape a dollar-sign. See Description Hi! I am running Docker Desktop for Mac: 4. So I want to run this: docker run -i -t --rm \\ -e " Learn how to correctly handle environment variables in Docker-Compose, including how to escape dollar signs and wrap values in quotes effectively. The documentation explains that $$ (double-dollar sign) can be used for escaping Docker Compose string interpolation. The problem is it has a $ in it, so the variable get evaluated but the $ is in the value so it tries to evaluate that afterwards. env file. To include a literal dollar sign in a In this guide, we'll explore how to properly escape dollar signs in Docker-Compose environment variables and ensure values are correctly wrapped in quotes without any unexpected characters. I Have variables in the . This also prevents Compose from interpolating a value, so a $$ allows you to refer to environment variables Compose processes any string following a $ sign as long as it makes it a valid variable definition - either an alphanumeric name ([_a-zA-Z][_a-zA-Z0-9]*) or a Docker Compose uses the dollar sign ($) for variable substitution, taking environment variables from a . - 'MYVAR=$GJ' will try to parse $GJ as a variable from the docker env file. 37. One with an exclamation mark ! and the other one with an ampersand &. The However, I'm not sure why the newline character is also escaped, as the COPY and RUN commands were merged into a single command. Yet another solution would be to run the docker container As Michael Friis from Docker pointed out, I’d missed the best option - combining escape and SHELL The SHELL instruction in a Dockerfile specifies According to the Docker Compose documentation, using a double-dollar sign ($$) should allow for a literal dollar sign and prevent Docker Compose from interpolating the value. env file : VAR1=docker321*! becomes You create a docker-compose with env_file providing variables to the inner container that are used as is without escape by the command directive to build the final container CMD instruction The arguments to bash -c are the script itself, followed by $0, $1, $2 etc. Stay up to date on Docker events Doesn't work. The double dollar sign will be replaced with a single $ upon running the command, which makes the shell And as the others in your comments say, you could also add the script via docker ADD or COPY in your Dockerfile and start it with docker RUN. I'm not an expert in escape characters and I might 1 Quote your string to include special characters in yaml like the #, and escape the dollar sign using a second dollar sign to prevent docker-compose from expanding it: (To understand why, realize that a build runs on the Docker engine, not in the client command line, and the engine can be a remote server. 2 (179585) The documentation explains that $$ (double-dollar sign) can be used for escaping Docker Compose string interpolation. You can use a $$ (double-dollar sign) when your configuration needs a literal dollar sign. env file with '*' and '!' chars in them. This should then pass the environment variable in the command to the container, I have a very simple shell script that should remove floating docker images, the command for this is: docker rmi $(docker images -f "dangling=true" -q) Now I'm running into an Thanks for the comment, I tried your approach but it didn´t work because of docker-compose: ERROR: Invalid interpolation format for "command" option in service "app-reverse-proxy". ${COMPOSER_HOME:-$$HOME/. e. This shoul 7 In a YAML file used by docker-compose, a single literal $ must be written as $$. Learn how to escape the dollar sign in command line arguments with examples and troubleshooting tips. config/compose}:/tmp One dollar before COMPOSER_HOME so it is interpolated from . I have a very simple shell script that should remove floating docker images, the command for this is: docker rmi $(docker images -f "dangling=true" -q) Now I'm running into an issue which I You can use a $$ (double-dollar sign) when your configuration needs a literal dollar sign. g. This also prevents Compose from interpolating a value, so a $$ allows you to refer to environment variables According to the Docker Compose documentation, using a double-dollar sign ($$) should allow for a literal dollar sign and prevent Docker Compose from interpolating the value. ---This vid It may be relevant to know that docker-compose and single quotes don't always mix; per the documentation: single quotes will take the string as is without unpacking the variable’s value. This feature . Problem is when running the container it puts quotes around the value so in the . env Two dollars before HOME so that it literally uses I am trying to put a password in a command in a Dockerfile.