I would instead specify what is allowed, which makes for a simpler regular expression in your case:

if($view_tag =~ m/\A[A-Za-z0-9][A-Za-z0-9_\-\.]+\z/) {
    # everything is OK
} else {
    die "Invalid/disallowed filename '$view_tag'";
};

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In reply to Re: Regex to detect file name by Corion
in thread Regex to detect file name by lirc201

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