The problem with tr/A-Za-z_.-//dc; is that the . character could be used to attempt to open the current or parent directory.

I'm paranoid enough to do something like 

tr/A-Za-z_.-//dc;
s/^\.+$//;

[download]
to make sure the user doesn't enter a string containing only dots.

In reply to Re: Re: How do you clean up user specified filenames? by tomhukins
in thread How do you clean up user specified filenames? by SilverB1rd

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