Assuming you have gotten $key and $value from the file, you could: 
$value =~ s((\$\{(\w+)\}|\$(\w+)))
           ($ENV{$2} or $ENV{$3} or $1)eg;

[download]
This would support an input file with two possible interpolations: 
key1=value
key2=value$key1
key3=${key1}value

[download]
It depends on the order of definition. You could iterate the replacement step across all strings until the keys stop changing, but that may raise new problems.

--
[ e d @ h a l l e y . c c ]

In reply to Re: Re: setting perl ENV from file by halley
in thread setting perl ENV from file by kcorcam

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