Re: Documentation of -atime, etc.

[Andreas Metzler]

On 2017-04-01 "Dale R. Worley" <address@hidden> wrote:
> I was looking at an old sandbox I have that contains some partially-made
> changes to the documentation of -atime and related predicates.

> In find.texi is:

>     @deffn Test -atime [+|-]n
>     @deffnx Test -ctime [+|-]n
>     @deffnx Test -mtime [+|-]n
>     True if the file was last accessed (or its status changed, or it was
>     modified) (exactly/more than/less than) n'
>     @var{n}*24 hours ago.  The number of 24-hour periods since
>     the file's timestamp is always rounded down; therefore 0 means ``less
>     than 24 hours ago'', 1 means ``between 24 and 48 hours ago'', and so
>     forth.  Fractional values are supported but this only really makes
>     sense for the case where ranges (@address@hidden and @address@hidden)
>     are used.
>     @end deffn
[...]
> My question is the measning of "Fractional values are supported but this
> only really makes sense for the case where ranges (@address@hidden and
> @address@hidden) are used."  What is the "vlaue" that it is
> talking about, is it the "n" in the predicate or the "number of 24-hour
> periods since ..."?  The meaning seems to be the former (since the
> latter would contradict how the atime value is computed), but the usage
> of fractional "n" would not seem to be very useful, since a fractional
> "n" could always be replaced with an integral "n" with the same effect.

Try it out. ;-) Starting with a directory of files with mtime x hours
+ a couple of minutes ago (x=1..48) and named as such:

address@hidden:/tmp/FFF$ find -mtime -0.5 -type f | sort
./01.hours-ago
./02.hours-ago
[...]
./10.hours-ago
./11.hours-ago
address@hidden:/tmp/FFF$ find -mtime 0.5 -type f | sort
./12.hours-ago
./13.hours-ago
[...]
./34.hours-ago
./35.hours-ago
address@hidden:/tmp/FFF$ find -mtime -1 -type f | sort
./01.hours-ago
./02.hours-ago
[...]
./22.hours-ago
./23.hours-ago

I gues it is not a very useful feature and it really hard to describe
properly imho.

cu Andreas
-- 
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