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<imap_timeoutimap_undelete>
^IMAP FunctionsLast updated: Mon, 26 Oct 2026

imap_uid

(PHP 4, PHP 5, PHP 7, PHP 8)

imap_uid — This function returns the UID for the given message sequence number

Description

function imap_uid(IMAP\Connection $imap, int $message_num): int|false

This function returns the UID for the given message sequence number. An UID is a unique identifier that will not change over time while a message sequence number may change whenever the content of the mailbox changes.

This function is the inverse of imap_msgno().

Parameters

imap

An IMAP\Connection instance.

message_num

The message number.

Return Values

The UID of the given message.

Changelog

Version Description
8.1.0 The imap parameter expects an IMAP\Connection instance now; previously, a valid imap resource was expected.

Notes

Note:

This function is not supported by POP3 mailboxes.

See Also

  • imap_msgno() - Gets the message sequence number for the given UID


<imap_timeoutimap_undelete>
^IMAP FunctionsLast updated: Mon, 26 Oct 2026