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Stream 'standard out' from System Exec

LV v7.0

When I run my external shell program I get a progress report as it is working. When I call it with LV (system exec) I can't see the progress report (standard out) until the process is over. Is there a way that I can have the system exec function stream the standard out to the string indicator?


Message Edited by Crickett on 04-19-2005 11:09 AM

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Message 1 of 6
Not as such, no.

What you can maybe do is re-route the output of the system call to a txt file (Add >textfile.txt) to the end of your command, and then read in the text file intermittantly.

Be aware that you may run into file-sharing problems though.

Would answer more detailed, but I have to finish up......


Using LV 6.1 and 8.2.1 on W2k (SP4) and WXP (SP2)
Message 2 of 6
And you would also need to set the wait until completion of System Exec to false.
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Is it really neccessary to set "Wait until complete" to false? What happens if you try to read the file parallel to the system command?

That's something I wouldn't have thought of.

Using LV 6.1 and 8.2.1 on W2k (SP4) and WXP (SP2)
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im thinking that an active x container with a wrapper of the cmd command would work best. ive found one but am not happy with it. i may venture writing my own. if someone has one or knows where a good one is, i'd love to see it.
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You're right, reading in parallel is something that I hadn't thought of. The only time I ever had to do do something like this was when the executable returned a completion string so I could start the task with wait set to false and then keep reading the text file until I saw the completion string. But doing it in parallel and stopping the file read when sytem exec is done should work just fine. I'll have to remember that if I ever have to do something like this again. Thanks.
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