you could just do
while(<*.old>){
    ($new = $_) =~ s/old$/new/;
    rename($_,$new);
}

[download]
And not waste space by bringing all those filenames into an array 

$_.=($=+(6<<1));print(chr(my$a=$_));$^H=$_+$_;$_=$^H;
print chr($_-39); # Easy but its ok.

[download]

In reply to Re: rename files in directory with new extenstion by damian1301
in thread rename files in directory with new extenstion by c

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