Your question is impossible to answer without knowing what you use to read in your config file. However, I suspect the module you use is "dumb" and won't do what you want it to do. It's up to the program to do it. 
# Use the appropriate syntax for your module:
my $root    = ...
my $code    = ...
my $include = ...
my $lib     = ...

foreach ($code, $include, $lib) {
   s/%ROOT%/$root/gi;
   
   # -or-
   #
   # $code =~ s/%([A-Z][A-Z_]*)%/
   #    if ($1 eq 'ROOT') {
   #       $root
   #    } elsif (exists($ENV{$1})) {
   #       $ENV{$1}
   #    } else {
   #       $1
   #    }
   # /eg
}

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In reply to Re: Config files by ikegami
in thread Config files by sparkel

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