Check another aMember database for existing username

I have two websites on different domains each with their own aMember installation and database. They both grant access to a third, separate database, where an account with a username and password gets generated on the third system.

Is there a hook or a way to check the username from aMember install on domain A against the aMember installation on domain B, and have the javascript and php on the signup form let the user know in real time whether or not that username is available or not?

Any suggestions would be welcome.

Thanks,
Brian

Just to clarify, I tried using the CHECK_UNIQ_LOGIN hook, and tried (simply) to return false, expecting the field to come back and say that the username already exists, but it is not seeming to do anything (in site.php file).

Does this look correct?

Am_Di::getInstance()->hook->add(Am_Event::CHECK_UNIQ_LOGIN, 'checkExternalLogin');
function checkExternalLogin(Am_Event_checkUniqLogin $event) {
return false;
}


Thanks,
Brian

Hi Caesar,

Thanks for helping out. When I try the code you supplied, I get a 500, with the following:
PHP Parse error: syntax error, unexpected '$e' (T_VARIABLE)

I notice that the function call is different from what I had - can you clarify the difference?

I appreciate your help.

Thanks,
Brian

Actually, I got it - I think there was a copy/paste error with the return carriages coming from here to my IDE.

Thanks so much, Caesar - I think this will work.

Best Regards,
Brian