When to use a variable in a bash command?

Jefferey Rosenbaum asked a question: When to use a variable in a bash command?
Asked By: Jefferey Rosenbaum
Date created: Tue, Jun 15, 2021 5:40 AM

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Top best answers to the question «When to use a variable in a bash command»

  • If you have a long command, or a set of commands. you can use variables. eg: subprocess and os.system () works fine when bash commands are simple and does not have brackets, commas and quotes.

FAQ

Those who are looking for an answer to the question «When to use a variable in a bash command?» often ask the following questions:

😳 How to execute a bash command saved in variable?

  • Another simple trick to run any (trivial/non-trivial) command stored in abc variable is: and push UpArrow or Ctrl-p to bring it in the command line. Unlike any other method this way you can edit it before execution if needed. This command will append the variable content as new entry to the Bash history and you can recall it by UpArrow.

😳 How do you assign a command to variable in bash?

  1. var=$(command-name-here) var=$(command-name-here arg1) var=$(/path/to/command) var=$(/path/to/command arg1 arg2) ...
  2. var=`command-name-here` var=`command-name-here arg1` var=`/path/to/command` var=`/path/to/command arg1 arg2`

😳 How to put output of a command into variable bash?

  • To assign output of any shell command to variable in bash, use the following command substitution syntax: var =$ (command-name-here) var =$ (command-name-here arg1) var =$ (/ path / to /command) var =$ (/ path / to /command arg1 arg2) OR use backticks based syntax as follows to assign output of a Linux command to a variable:

Question from categories: shell variables linux shell commands cheat sheet shell script bash logo shell command icon

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