ZBasic System Library
218
ZBasic Microcontrollers
Type
Subroutine
Invocation
PeekQueue(queue, var, count)
Parameter
Method
Type
Description
queue
ByRef
array of Byte
The queue from which to retrieve data.
var
ByRef
any type
The variable to receive the retrieved data.
count
ByVal
int16
The number of bytes to retrieve.
Discussion
This routine will copy the specified number of bytes from the queue to the indicated variable but it does
not remove them from the queue. The routine will not return until it can copy the entire number of bytes
specified. Because of this, you should usually check the number of bytes available in the queue using
GetQueueCount() before calling PeekQueue().
Note that if the calling task is locked and the queue contains insufficient data when this routine is called,
the task will be unlocked to allow other tasks to run.
Caution
If the requested number of bytes is larger than the queue capacity, the routine will never return. Likewise,
if not enough data is placed in the queue, the routine will never return. Also, if the variable to receive the
data is smaller than the number of bytes indicated, adjacent memory will be overwritten, usually with
undesirable results.
Example
Compatibility
BasicX allows any type for the first parameter. The ZBasic implementation requires that it be an array of
Byte.
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