Re^2: How to check if a file is modified or missing on windows server using a perl script

Checksum is probably good enough (1/256 chance of undetected change if done as an 8 bit ASCII checksum) especially if you also check file size. A CRC module would probably give you even more accurate results if you need to be that specific.

Comment on Re^2: How to check if a file is modified or missing on windows server using a perl script

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Re^3: How to check if a file is modified or missing on windows server using a perl script by Laurent_R (Canon) on Nov 02, 2013 at 09:46 UTC
Yes, checking the file size (and also last modification time) certainly adds quite a bit of reliability (and is fast), and that alone may actually be sufficient for the purposes of crazy-duck, but when I mentioned checksum, I used the word as a general term for describing the overall techniques of digital "footprints", digests or signatures. I am using on some of my platforms "checksum" utilities actually implementing a CRC-32 algorithm, where the chances of undetected change are 1 in billions (at least in theory).	[reply]
Re^4: How to check if a file is modified or missing on windows server using a perl script by marinersk (Priest) on Nov 03, 2013 at 01:13 UTC
Yes, I tend to use external utilities as well; specifically ones which yield the same results on Linux and Windows. If you have any module suggestions for CRC-32 I would be interested in stealing from your experience base. :-)	[reply]
Re^5: How to check if a file is modified or missing on windows server using a perl script by Laurent_R (Canon) on Nov 03, 2013 at 10:04 UTC
Well, there are some CRC modules on the CPAN such as String::CRC32 or Digest::CRC, but I have never installed nor used them. I only very occasionally use these digital signature utilities to check file integrity between VMS and Unix platforms (or different Unix platforms), but I never had to do it on a regular basis.	[reply]