(PHP 4, PHP 5, PHP 7)
imap_setflag_full — Sets flags on messages
$imap_stream
   , string $sequence
   , string $flag
   [, int $options = NIL
  ] )
   Causes a store to add the specified flag to the
   flags set for the messages in the specified 
   sequence.
  
imap_streamAn IMAP stream returned by imap_open().
sequenceA sequence of message numbers. You can enumerate desired messages with the X,Y syntax, or retrieve all messages within an interval with the X:Y syntax
flagThe flags which you can set are \Seen, \Answered, \Flagged, \Deleted, and \Draft as defined by » RFC2060.
optionsA bit mask that may contain the single option:
ST_UID - The sequence argument contains UIDs
          instead of sequence numbers
         
        
   Returns TRUE on success or FALSE on failure.
  
Example #1 imap_setflag_full() example
<?php
$mbox = imap_open("{imap.example.org:143}", "username", "password")
     or die("can't connect: " . imap_last_error());
$status = imap_setflag_full($mbox, "2,5", "\\Seen \\Flagged");
echo gettype($status) . "\n";
echo $status . "\n";
imap_close($mbox);
?>