I think it would be valuable to write all IPs to a file. Have a space separating the IP from the USER_AGENT on each line. Then suck each line into a regex like /(\S+)\s(.*)/ so that $1 has the IP and $2 is the rest of the info you'd want to store about each session. Make a hash $visitlog{$1}=$2 for each line. When you get a new submission, check 
if (defined $visitlog{$newipadd}) {
  # maybe check $USER_AGENT && $othrsave stuff to examine
  # if anything further about unique proxy users can be determined
  #failure code && error mesg
} else {
  # maybe check $USER_AGENT && $othrsave stuff to further
  # determine if the user is attempting to revote.
  #process vote && success mesg
  $visitlog{$newipadd} = "$USER_AGENT" . $othrsave;
}

[download]
Then before you end the script, overwrite your logfile with the current visitlog hash with each line containing "$key $value". This is how I'd probably do it. Hope it's helpful. I'd be glad to try to help more if you'd like any. TTFN & Shalom.

-PipTigger

In reply to Re: Quick and easy way to prevent multiple votes? by PipTigger
in thread Quick and easy way to prevent multiple votes? by Anonymous Monk

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