![]() ![]() ![]() We can access bash environment variables only one way the parent shell exports its variables to the child shell’s environment, but the child shell can’t export variables back to the parent shell. However, if we compare bash environment variables to programming language global variables, there’s one main distinction. Environment variables (defined with export) are like global variables that we can access within the defining shell and all its child shells, processes, and commands. In order to check your installation you can use.Shell variables (defined without export) are like local variables that we can access only within that shell.If we compare bash variables to variables in programming languages: the rest of the documentation, we will be primarily using ES modules syntax. ![]() Any child shells, processes, or subsequent commands can’t access it: $ MYVAR=1729 If you are already familiar with Node.js and the concept of build tools. Let’s contrast this with the shell variable defined without export, which is only available in that shell. The export attribute marks MYVAR for automatic export to the environment of the child processes created by the subsequent commands: $ export MYVAR=1729 This command does that by setting the export attribute for the shell variable MYVAR. The main difference between these two is that the export command makes the variable available to all the subsequent commands executed in that shell. It creates a variable named MYVAR, assigns it the value 1729, and marks it for export to all child processes created from that shell. ![]() The second definition with the export command is another way of defining a variable. ![]()
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