Unzip files within labview

I have been playing around with the new zip functions in labview 8. I like it, nice and simple. Then I realized something. They don't have any functions listed to unzip files?!?! Am I missing something, or is there another method to call zip files in labview, unzip to a location, and then grab files from the unzip within labview programatically? The only method I can think of is to have winzip installed on the machine so you can use the command line execute function (but that is an awful method IMHO). I would have thought that if NI got the license to build zip files they would have also gotten the rights to include the unzipping as well.

Mads wrote:
Unzip functions in native G would be very useful, simply because that code is supported on the RT targets. There is an unzip option in the palette in LV 8.5, but it returns error 2 if I try to unzip anything with it...if the file only contains one file it works, but it retunrs the error and with more than one file inside the archive it fails....is it supposed to work, or is there still no proper unzip support?
I have code I want to move from a PC to a RIO unit, but the lack of a G-version of unzip makes this difficult, the OpenG alternative is not native G so no luck there...It seems the VIs available in LV 8.5 could do the job, if only some minor bug-fixing was done(?)
ZIP/Unzip support as native VIs is not very practical. Compression is a very tricky business and developing such algorithmes in a way that always works is not very easy and quite time consuming, not to mention that LabVIEW is not the ideal invironment to do low level bit shuffling and manipulation.
Combine that with the fact that there are ready made and VERY throughly tested open source libraries with the needed functions (of course mostly in C) and you really realize that trying to reinvint that wheel in LabVIEW itself is simply an exercise in vain.
The OpenG ZIP/UNZIP library is based on the wide spread zlib library that just about compiles on any C compiler that dates from after the early 1960ies and so it should be no problem to grab the according C source code from the OpenG Toolkit depository on sourceforge.net and recompile it with the correct C toolchain for your CRIO realtime target.
Oh and if you mean to transport the unzip algorithme to the FPGA target instead of the realtime target, keep dreaming. Once the FPGA chips start to reach the 1 Billion gate count this could actually start to get feasable. 3 Million gates is really nothing for such a task.
Rolf Kalbermatter
Message Edited by rolfk on 11-28-2007 11:22 AM
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

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Happy Holidays
"Enrique" wrote in message
news:[email protected]..
> I see...
>
> After doing some research, it seems to me that there is no easy way to
> find out the type of data, other than looking at the header file and
> have documents like Using External Code in LabVIEW handy. The
> following information is from that document:
>
> LVBoolean is an 8-bit integer. 1 if TRUE, 0 if FALSE.
>
> LabVIEW specifies file refnums using t
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>
> From the header file, is can be deduced that TD1 is a cluster in
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