What is Variable Expansion in Bash ?

Bash Liste Des Attaques Ovh


variable expansion is an expansion that replaces a variable expression by its value.


Prerequisite: We set the value of the variable foo to bar to perform the expansion



  • In the following expression that is composed of:
echo ${foo}
  • The variable expression foo will be replaced / expanded by the value bar at runtime resulting to
echo bar

that outputs to the console


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