Is it safe to use rsync when the source filesystem is mounted and writeable, assuming that it may very well be modified while rsync is running? I presume that under race conditions I may not get the latest modifications, but is there any risk of corruption?
Considering this Q&A about the order of execution in the shell as it relates to redirection, and despite the fact that if a file doesn’t exist it gets created first so that cat example.txt | shuf > example.txt doesn’t complain that the file doesn’t exist – which just confirms the order from what I understand – then why is it that about once every thousand times on my system the shuffle works when I do this (backup contains 15 static values each on their line)