Lots and lots of very pertinent replies on the security problems relating to the task you have mentioned.

The only thing I haven't seen mentioned, which it looks like you need, is to check that the directory exists. Presumably your code is not just supposed to work for Laura, so unless you are anticipating all the required directory and subdirectory names, you will need to create them on the fly.

Small snippet:
print "Directory $dirname does".((-d $dirname)?" ":" not ")."exist.\n";

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