f



"re-entrant" "file I/O" "QSM_State Machines"

 
 
I have trouble with writing (appending) to text file in a QSM that is in an "occurence mode" of operation whereby the queue waits for outside engueue to go ahead and do a task. The task is simply to write to a file a line of text.
 
Outside producers give the queue its go ahead and data is sent along etc...
 
WHat I am seeing in the logging functions are multiple errors (Error 1)
Somehow Labview is not noticing that the reference is valid or it is invalidating the reference.
 
Q is Should I just let the QSM loop to keep it alive and would that work?
 
What is the rule concerning queue waiting for an event? Does the VI get flagged as idle and is that why the ref appears to be dropped?  THere is no reason I can think of for the ref to be dropped. It is opened in the init frame then kept in a shift register.
and available at each iteration in the QSM.
 
The example works in a simple loop but not a loop that is waiting on an occurence.  Why?
 
The only work around I can manage is to use the path and open the reference when it is not valid which feels kind of  silly if you get my drift
 
Anyone seen this before?
 
Thank You
 
 
 
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x9561 (148441)
12/4/2007 4:40:07 AM
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