You can use an onClick or onChange to execute a cgi-script by using redirection: 
<HTML>
<HEAD></HEAD>
<BODY>
<SCRIPT Language="Javascript">

function go_to() {
    document.location = "http://your-cgi-script.cgi";
}

</SCRIPT>

<IMG SRC="BLAH" onClick="go_to()">
</BODY>

[download]
Follow the good advice the others have given you for the script at the other end and you should be good to go.

In reply to Re: javascript by faerloche
in thread Executing CGI script via Javascript by Anonymous Monk

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