I was given the task of accepting a file containing lines which might have one or occurrences of Environment variables defined as ${VAR}. I have to translate within the file all those variables into the environment variable which is defined. My solution was:

perl -i -n -e '
while ($_ =~ /\${([^\$]*)}/g) {
        $s = "\\" . $&; 
        $t = $ENV{$+};
        s/$s/$t/e;
} print $_;' file

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Is there an better way?
moshefr

20040517 Edit by Corion: Added formatting

In reply to Translating Env Variables by moshefr

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