#!/usr/bin/perl

#Some code to read arguments passed to the script
#Read STDIN (GET & POST) into %input hash

if ($input{'file'} !~ /^\// && $input{'file'} !~ /\.\./) {
open FILE, ">/home/user/www-root/users/files/$username/$input{'file'}" or die "Error opening file!";
print FILE $input{'file_contents'};
close FILE;
} else {
#produce some error denying access to this file
}