array|bool getHeaders(int &$mid, [str &$pid = "0" [, bool $rtn = FALSE [, array $args = array()]]])

Sets $header property with various header information gathered from the message. This information is stored in the $header property as a multideminsional array, base-level nesting is offset by message id, sub-level is associative via the type of header information, and a third level of nesting is present for addresses, numbered offset by the address count. See the $header property for the specific header information gathered.

If the optional $rtn argument is TRUE, the contents of the $header property are returned, $rtn is FALSE by default.

The optional $args argument accepts an associative array used to specify three optional arguments of imap_headerinfo and one optional argument of imap_rfc822_parse_headers. array("from_length" => 1024) sets the $from_length argument of imap_headerinfo. array("subject_length" => 1024) sets the $subject_length argument of imap_headerinfo. array("default_host" => "unknowndomain.com") sets the $default_host argument of both imap_headerinfo and imap_rfc822_parse_headers.

Use the $option property or the Mail_IMAP::setOptions method to set optional arguments for imap_fetchheader or imap_fetchbody, which are both called on in Mail_IMAP::getRawHeaders, which is called on by getHeaders.

getHeaders calls on Mail_IMAP::_checkIfParsed, Mail_IMAP::getRawHeaders and Mail_IMAP::_parseHeaderLine internally.