MD5 on large files

[Lackel]

Hello,

I want to use the MD5 function to check very large files, but the Labview MD5 function does'nt return the same value as other programs on large files:

File master_ftyplavb.bin.tar.gz >> size (compressed 800MB)  897 435 615 bytes 

MD5 with Labview routine (Win7) 2257553958b07abe84e0bf8e4fb167a8

MD5 withmd5sum (Linux)             2257553958b07abe84e0bf8e4fb167a8

MD5 with md5sums (Win7)           2257553958b07abe84e0bf8e4fb167a8

File master_ftyplavb.bin >> size  (uncompressed 8GB) 7 948 206 080 bytes 

MD5 with Labview routine (Win7) bf349e79d7450c2746d968e81563939b

MD5 withmd5sum (Linux)             609e698b87e10ec4506e1eb465461d06

MD5 with md5sums (Win7)           609e698b87e10ec4506e1eb465461d06

Is there an issue with this routine?

Regards

[PhillipBrooks]

The built in function is strictly written in LabVIEW, it may have something to do with your file size exceeding max for U32.

I've attached a VI that calls the .NET MD5 function to evaluate a given file name. (LV 8.6)

[Lackel]

It is working fine.

Thank you!

[CMal]

Thanks for reporting this issue.  Like Philip guessed, it is caused a part of the code that assumes the file size can be represented by a U32 integer, so it is failing with any file larger than 4 GB.  This has been reported to R&D in CAR 378947.

Chris M

[Jeff-P]

CAR 378947 discussed in this thread has been fixed in LabVIEW 2013. For a more complete list of bugs fixed in LabVIEW 2013, check the LabVIEW 2013 Bug Fixes. You can download an evaluation copy of LabVIEW 2013 at http://www.ni.com/trylabview/ or if you have an earlier version of LabVIEW installed and an active SSP subscription, you will be able to download the latest version of LabVIEW through NI Update Service.

Jeff Peacock

Product Support Engineer | LabVIEW R&D | National Instruments