RT BUG ? Problem with simultaneous access of different files under RT 7.1

[lraynal]

Dear all,
I get a crash-bug under RT 7.1, when I'm accessing 2 differents files, from 2 differents thread, but at the same time. The desktop computer (which is under RT 7.1) just blocks...
On one thread I was writting an INI file and on the second thread I was writting a standard text file...

Is this a known bug? Is there a way to get around it (upgrading to 7.1.1, using semaphore for a sequential access of any files, etc. ?)
Does someone has ever heard about this bug???

Thank you for your advices.
Laurent

[lraynal]

I just find out that LabVIEW RT does not use any cache, wich means that every write and read operation requires an access to the disk...
Then NI recommend to write out data one sector at a time (or let's say one file at a time...)

I'm then going to use semaphore to prevent double access to the disk!

But, does anyone has an other idea on how to solve or prevent this problem? (LabVIEW RT 7.1.1 for example?)

Thank you for your feedback.
Laurent

Here is the link to the tutorial talking about this: http://zone.ni.com/devzone/cda/tut/p/id/3746

[Ben]

I saw an issue with one files contents being written to another file that was open at the same time. This occured in an app that has dozens of files open and create new files sets periodically. My customer suspected this was the cause of a number of earlier file corruption events. It appears the file refnums somehow got cross-wired inside the FIle I/O API.

Aside from myself I have never heard anyone else notice this issue. It was fixed in LV 8 (?)

If you are seeing the same thing I saw, then semaphores will not help (I was using them and still got the corruption).

Ben