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Top Forums UNIX for Dummies Questions & Answers Expanding variables with Ed Bash 3.2.33 Post 302339885 by de_la_espada on Friday 31st of July 2009 03:58:26 PM
Old 07-31-2009
Expanding variables with Ed Bash 3.2.33


The following code finds the line containing fruits in test.txt and replaces instances of apple with banana.

   ed -s test.txt <<< $'/fruits/s/apple/banana/g\nw'

What I want to do is put variables in the place of fruits, apple and banana.

I have tried replacing ' with " to get the variables to expand, but to no avail.

ed -s accounts.txt <<< $"/$account/s/$balance/$newBalance/g\nw"

ed -s accounts.txt <<< $"/${account}/s/${balance}/${newBalance}/g\nw"

And trying to echo them, but still no luck.

I'm using GNU bash, version 3.2.33(1)-release (i386-redhat-linux-gnu)
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bool array_walk_recursive NULL (array &$array, callable $callback, [mixed $userdata]) DESCRIPTION
Applies the user-defined $callback function to each element of the $array. This function will recurse into deeper arrays. PARAMETERS
o $array - The input array. o $callback - Typically, $callback takes on two parameters. The $array parameter's value being the first, and the key/index second. Note If $callback needs to be working with the actual values of the array, specify the first parameter of $callback as a refer- ence. Then, any changes made to those elements will be made in the original array itself. o $userdata - If the optional $userdata parameter is supplied, it will be passed as the third parameter to the $callback. RETURN VALUES
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