The SYS(2007) function can create crc16 or crc32 depending on the parameter passed. At most it can return 2^16-1 and 2^32-1 different values respectively. It's quite possible that 2 files can have the same checsum returned by SYS(2007). I would recomend to use one of the Hash algorithm that return longer digest of the file. You can use Craig Boyd's Vfpencryption.fll to generate MD5 or stronger hash.

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>I can use FILETOSTR(), low level file access or FC.exe to compare 2 text files and know if they are same. I was curious if SYS(2007, FILETOSTR("MyFile.txt")) help me in this matter by comparing with a previously generated checksum value.
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>My concern being small, say a single character, change to a big text file will guaranteed return a different checksum value?
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>UPDATE, just thought this question. What are the chances that 2 different text files might return a same value?
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