(PHP 4, PHP 5, PHP 7, PHP 8)
imap_headers — Returns headers for all messages in a mailbox
Returns headers for all messages in a mailbox.
   Returns an array of string formatted with header info. One
   element per mail message.
   Returns false on failure.
  
| Version | Description | 
|---|---|
| 8.1.0 | The imapparameter expects an IMAP\Connection
  instance now; previously, a resource was expected. |