Short of checking every single byte against each other you need to do some sort of short hand. “Assume these two files are the same, check if they either syste

Short of checking every single byte against each other you need to do some sort of short hand. “Assume these two files are the same, check if they either system is saying they have modified it or check if the size has changed and call it a day” is pretty fair of an assumption and something even I knew RSync is doing and I’ve only used it once in a project 10 years ago. I am sure Rachel also knows this. So, what is the problem? Is data not being synced? Is data being synced too often? And why do these assumptions lead to either happening? What horrors is the author expecting the reader to see when running the suggested command? That is what is not explained in the article.