Timestamp of file wasn't updated


We notice that timestamp of file wasn’t updated when we modified files without changing his size significantly (we think not a octect but some octect whitout changing the sector reservation). It’s a problem for us to know the date of last modification of files and for backup (robot us this timestamp to know if a file was modified).


Does the same kind of behaviour occur on your system when saving a file locally (to an internal hard drive) ?