Take a look at the 'rename' function (perldoc -f rename). 
foreach my $file (glob '/path/*.txt') {
    (my $new_file = $file) =~ s{txt\z}{html};
    rename $file => $new_file;
}

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In reply to Re: How can i change the file extension? by Anonymous Monk
in thread How can i change the file extension? by littlemonk

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