I think I'd use something simple like: 

my $file = ...;
my $n=0;
if( -e $file ) { ## Stop endless loop if $file doesn't exist
    $n++ until rename $file, "$file.bak$n";
}
else {
    die "$file doesn't exist";
}
my $backup = "$file.bak$n";

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"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
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In reply to Re^3: Copying a file to a temporary file by BrowserUk
in thread Copying a file to a temporary file by shay

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