Bash indirect variable referencing

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Use bash indirect variable reference:

${!var}

And of course can be done with eval, not recommended:

eval 'echo $'"$var"

Why:

$ bar=xyz

$ var="bar;whoami"

$ eval 'echo $'"$var"
xyz
spamegg

Th command whoami is being evaluated too as part of evaluation by eval, imagine a destructive command instead of whoami.

Example:

$ bar="xyz"

$ var=bar

$ echo "${!var}"
xyz

$ eval 'echo $'"$var"
xyz

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