CANDE can execute an unlimited number of queued entries. Queued input is in one of three states: normal, pending, or waiting.
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The normal state occurs when CANDE is busy executing a command for a station and another command is entered before the first is completed. The message “#QUEUED” is issued to the user, indicating that the new command has been placed in the input queue. If the currently executing command completes normally, then the first queued command becomes the currently executing command, and so on. If an error occurs on the currently executing command and queued input exists, the queued input is then either pending or waiting. (Refer to the QWAIT option below.)
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The pending state occurs if a “#QUEUED INPUT PENDING” message is given; if a normal line of input is entered after the message, then the queued input is discarded and the session continues with that line of input. If the queued input should not be discarded, then one of the queue manipulation commands can be used and the input queue can be set to the waiting state.
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In the waiting state, any normal line of input is queued at the end of the queue and the message “#QUEUED” is given. A “#QUEUED INPUT WAITING” message is then displayed. The state of the queued input remains waiting until a ?GO, ?PURGE, or ?REPEAT command is issued.
While the state of the queued input is waiting or pending, queued input entries can be entered, removed, or edited. Insertion of an entry specifies that CANDE is to wait for intervention before performing that entry or that the session is resumed with the first entry in the queue or with the saved text.
Certain queue manipulation commands are limited to operation on the visible portion of the user's queue. Only the first 20 entries of the user's queue are visible.
QWAIT is a user option that is set or reset with the SO (or ?SO) and RO (or ?RO) commands, respectively. If QWAIT is set and an error occurs, the state of the user's queued input is set to waiting; otherwise, it is set to pending.
The commands provided for manipulation of queued entries are ?GO, ?WAIT, ?PURGE, ?TAKE, and ?ENTER.
