in reply to why does open ">..." sometimes touches the directory?
Probably the safest assumption is simply to assume that “it might.” Actual behavior can depend on the OS-type and, within Unix/Linux, exactly what filesystem is used and how that filesystem is configured. All of which is really beyond your control. So, don&rquo;t get upset if the mod-time of a directory changes, and, don’t use mod-time as a sentinel to tell you whether or not you need to dumpster-dive into a particular directory.
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