php - need to add in_reply_to when using imap_append -
i`m trying append mail after send in sent mailbox... public function append_mail($mail_box, $replyto, $from, $to, $subject, $text, $attaches = []){ $mailbox = "{".$this->imap_host.":".$this->imap_port.$this->imap_path."}".$mail_box; $dmy = date("d-m-y h:i:s"); $boundary = "------=".md5(uniqid(rand())); $msgid = $this->generatemessageid(); $msg = "from: $from\r\n"; $msg .= "to: $to\r\n"; $msg .= "date: $dmy\r\n"; $msg .= "message_id: $msgid\r\n"; $msg .= "in_reply_to: $replyto\r\n"; $msg .= "subject: $subject\r\n"; $msg .= "mime-version: 1.0\r\n"; $msg .= "content-type: multipart/mixed; boundary=\"$boundary\"\r\n"; $msg .= "\r\n\r\n"; $msg .= "--$boundary\r\n"; $msg .= "content-type: text/