On 01/19/2013 01:21 PM, John Hinton wrote:
On 1/19/2013 1:28 PM, Nicolas Thierry-Mieg wrote:
See man rsync: Rsync finds files that need to be transferred using a “quick check” algorithm (by default) that looks for files that have changed in size or in last-modified time.
and yes I've tested this before posting ;-)
to avoid this you need to use --size-only .
Yet size only is not reliable. If for instance you have a simple text file with the word hellO and someone catches the typo and changes it to hello, the filesize doesn't change as near as I can see. Both show as 6 using ls -al. Unless rsync uses a more granular check of filesize that I am not aware of? If this is the case, then someone could potentially edit a large document fixing numerous simple typos and wind up with the same filesize.
And then there is prelink, which changes the contents of files without changing either the size** or the modification time. It's the topic of some very messy code and nasty comments in my backup scripts.
** The very first time a file is prelinked, the size will change. Subsequent prelink runs may change the content, but will not affect the size.