6 views 
Summery Summery
Extract and return the ID of the last SMTP transaction based on a list of patterns provided in SMTP::$smtp_transaction_id_patterns.
Syntax Syntax
Description Description
Relies on the host providing the ID in response to a DATA command. If no reply has been received yet, it will return null. If no pattern was matched, it will return false.
Return Return
(bool|null|string)
Source Source
File: wp-includes/class-smtp.php