# no .. / ` \
die "no .. \/ \` \\ allowed in node name.\n" if ($node =~ /(\.\.|\/|\`
+|\\)/);
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I strongly reccomend adding this snippet to this program if you are placing this on the public internet. Do not evaluate $node and run an open statement without doing more sanity checking on whats being sent your way. Making a node as ../data/test would work. With this, it would get shot down before the open call.