labview dll fails to work while original VIs work perfectly

[Milas]

Hello, I have a little problem to which I have no clue. I have compiled a project to a DLL ant tested it with a test VI. While the test VI runs perfectly when calling other VIs it freezes when calling the DLL. Has anyone an idea ?

It works like this. I start initializing the references to four ActiveX controls and then begin to dump video files on my disk and write the metadata in a database. Then I launch a VI that commands the process to stop when pressing on the stop button.



Thanks a lot

Milas

[Milas]

Oh and the database continues to be filled while labview is frosen. It however gives me an error flag indicating that no video is being saved on my HD. It seems that the DLL fails to give commands to the ActiveX via the references. Hope you can help me.

[MikeS81]

Hi Milas,

what shows your picture? Is it only one vi, or are this the two versions? You have no defined dataflow in the upper case structure.

Mike

[Milas]

Hi Mike, thanks for your answer

This is the same VI, I made it in order to compare what happens in the case I use my vi's and the in the case I use my dll. It's true that in the upper case there is no defined dataflow but it seem to work perfectly. Consider the "init ref" vi as a non-reentrant global variable which is reused in the "begin service" vi and the "end service" vi as a way of setting a flag in the "begin service" vi in order to stop it.

The dll functions used in the lower case are the same as the vi's in the upper case.

The begin service takes the references of the activex and starts recording a video from an Axis IP video server. After each sequence, it stores metadata in a postgresql database and dumps the video block on the hard disk. When running the dll, the activex seems not to work as the metadata is still dropped in my database with an error flag indicating that the video has not been recorded (and the video files are not on the disk).

If you have an idea of how to resolve the problem, it would be wonderful.

Thanks in advance
Milas


Message Edited by Milas on 06-26-2008 09:59 AM