PHP Manual: imap

function imap_close(IMAP\Connection $imap, int $flags = 0): true

Closes the imap stream.

imap: An IMAP\Connection instance.
flags: If set to CL_EXPUNGE, the function will silently expunge the mailbox before closing, removing all messages marked for deletion. You can achieve the same thing by using imap_expunge()

Always returns true.

Throws a ValueError if flags is invalid.

Version	Description
8.1.0	The `imap` parameter expects an IMAP\Connection instance now; previously, a valid `imap` resource was expected.
8.0.0	A ValueError is now thrown on invalid `flags` parameter values. Previously, a warning was emitted and the function returned `false`.

imap_close