Lo siguiente solo usa los tipos mime para validar un archivo, luego verifica el tamaño de ambos. Para obtener una lista de la mayoría de los tipos mime, consulte aquí o google.
function allowed_file(){
//Add the allowed mime-type files to an 'allowed' array
$allowed = array('application/doc', 'application/pdf', 'another/type');
//Check uploaded file type is in the above array (therefore valid)
if(in_array($_FILES['resume']['type'], $allowed) AND in_array($_FILES['reference']['type'], $allowed)){
//If filetypes allowed types are found, continue to check filesize:
if($_FILES["resume"]["size"] < 400000 AND $_FILES["reference"]["size"] < 400000 ){
//if both files are below given size limit, allow upload
//Begin filemove here....
}
}
}
