A good and reasonably fast checksum like MD5 sounds like a good idea.

But first, I would just check the files' modification times. (see -M and possibly -C) Depending on the OS and filesystem, it can be safe to assume that a file hasn't changed if either none of these have changed, at least not if you check only once a day (since the change time might only have a one second resolution).

Checking the -C and -M attributes will be a lot faster than checking the file's data contents for large files.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: (OT) indexing pdf archive content in a multiuser environment- how do i know when the content changed? by Joost
in thread (OT) indexing pdf archive content in a multiuser environment- how do i know when the content changed? by leocharre

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