- mailbox-cursor-next MAILBOX-CURSOR #!optional TIMEOUT DEFAULTprocedure
Returns the next object in the mailbox queue, waiting if necessary.
The mailbox queue is scanned from oldest to newest.
TIMEOUT is a SRFI-18 time object or the real number of seconds.
Should TIMEOUT be specified and occur the DEFAULT, if supplied, will be returned. Otherwise a mailbox timeout exception will be signaled for the calling thread. The DEFAULT value cannot be (void).