Bash: how to get the value of a variable if its name is in another variable

Question

PowerShell

Available:

my_param="123"
param="my_param"

How can I get the value of the $my_param variable via $param?

Answer 1

# eval a=\$$param
# echo $a
123

Answer 2

From bash 2, you can use the ${!variable} notation
$ echo ${!param}
123

Answer 3

Something like

my_param="123"
param=`echo $my_param`