&reftitle.constants; &extension.constants;

`NIL` (`int`)

- Deprecated as of PHP 8.1.0.

`OP_DEBUG` (`int`)

`OP_READONLY` (`int`)

- Open mailbox read-only

`OP_ANONYMOUS` (`int`)

- Don't use or update a `.newsrc` for news (NNTP only)

`OP_SHORTCACHE` (`int`)

`OP_SILENT` (`int`)

`OP_PROTOTYPE` (`int`)

`OP_HALFOPEN` (`int`)

- For IMAP and NNTP names, open a connection but don't open a mailbox.

`OP_EXPUNGE` (`int`)

`OP_SECURE` (`int`)

`CL_EXPUNGE` (`int`)

- silently expunge the mailbox before closing when calling `imap_close`

`FT_UID` (`int`)

- The parameter is a UID

`FT_PEEK` (`int`)

- Do not set the \Seen flag if not already set

`FT_NOT` (`int`)

`FT_INTERNAL` (`int`)

- The return string is in internal format, will not canonicalize to CRLF.

`FT_PREFETCHTEXT` (`int`)

`ST_UID` (`int`)

- The sequence argument contains UIDs instead of sequence numbers

`ST_SILENT` (`int`)

`ST_SET` (`int`)

`CP_UID` (`int`)

- the sequence numbers contain UIDS

`CP_MOVE` (`int`)

- Delete the messages from the current mailbox after copying with `imap_mail_copy`

`SE_UID` (`int`)

- Return UIDs instead of sequence numbers

`SE_FREE` (`int`)

`SE_NOPREFETCH` (`int`)

- Don't prefetch searched messages

`SO_FREE` (`int`)

`SO_NOSERVER` (`int`)

`SA_MESSAGES` (`int`)

`SA_RECENT` (`int`)

`SA_UNSEEN` (`int`)

`SA_UIDNEXT` (`int`)

`SA_UIDVALIDITY` (`int`)

`SA_ALL` (`int`)

`LATT_NOINFERIORS` (`int`)

- This mailbox has no "children" (there are no mailboxes below this one).

`LATT_NOSELECT` (`int`)

- This is only a container, not a mailbox - you cannot open it.

`LATT_MARKED` (`int`)

- This mailbox is marked. Only used by UW-IMAPD.

`LATT_UNMARKED` (`int`)

- This mailbox is not marked. Only used by UW-IMAPD.

`LATT_REFERRAL` (`int`)

- This container has a referral to a remote mailbox.

`LATT_HASCHILDREN` (`int`)

- This mailbox has selectable inferiors.

`LATT_HASNOCHILDREN` (`int`)

- This mailbox has no selectable inferiors.

`SORTDATE` (`int`)

- Sort criteria for `imap_sort`: message Date

`SORTARRIVAL` (`int`)

- Sort criteria for `imap_sort`: arrival date

`SORTFROM` (`int`)

- Sort criteria for `imap_sort`: mailbox in first From address

`SORTSUBJECT` (`int`)

- Sort criteria for `imap_sort`: message subject

`SORTTO` (`int`)

- Sort criteria for `imap_sort`: mailbox in first To address

`SORTCC` (`int`)

- Sort criteria for `imap_sort`: mailbox in first cc address

`SORTSIZE` (`int`)

- Sort criteria for `imap_sort`: size of message in octets

`TYPETEXT` (`int`)

- Primary body type: unformatted text

`TYPEMULTIPART` (`int`)

- Primary body type: multiple part

`TYPEMESSAGE` (`int`)

- Primary body type: encapsulated message

`TYPEAPPLICATION` (`int`)

- Primary body type: application data

`TYPEAUDIO` (`int`)

- Primary body type: audio

`TYPEIMAGE` (`int`)

- Primary body type: static image

`TYPEVIDEO` (`int`)

- Primary body type: video

`TYPEMODEL` (`int`)

- Primary body type: model

`TYPEOTHER` (`int`)

- Primary body type: unknown

`ENC7BIT` (`int`)

- Body encoding: 7 bit SMTP semantic data

`ENC8BIT` (`int`)

- Body encoding: 8 bit SMTP semantic data

`ENCBINARY` (`int`)

- Body encoding: 8 bit binary data

`ENCBASE64` (`int`)

- Body encoding: base-64 encoded data

`ENCQUOTEDPRINTABLE` (`int`)

- Body encoding: human-readable 8-as-7 bit data

`ENCOTHER` (`int`)

- Body encoding: unknown

`IMAP_OPENTIMEOUT` (`int`)

`IMAP_READTIMEOUT` (`int`)

`IMAP_WRITETIMEOUT` (`int`)

`IMAP_CLOSETIMEOUT` (`int`)

`IMAP_GC_ELT` (`int`)

- Garbage collector, clear message cache elements.

`IMAP_GC_ENV` (`int`)

- Garbage collector, clear envelopes and bodies.

`IMAP_GC_TEXTS` (`int`)

- Garbage collector, clear texts.