Re: [Help-bash] bash native way to support test file is older than a certain period of time

[Andreas Kusalananda Kähäri]

On Mon, Jun 10, 2019 at 09:06:57AM -0400, Greg Wooledge wrote:
> On Sun, Jun 09, 2019 at 10:51:51PM +0200, Andreas Kusalananda Kähäri wrote:
> > The other alternative is to use find:
> > 
> >     if [ -n "$( find "$myfile" -mmin +60 -print)" ]; then
> >         echo file was modified more than 60 minutes ago
> >     fi
> > 
> > (where "$myfile" is some path to a file)
> > 
> > There's nothing "bash native" about that though, but it would be
> > portable.
> 
> Portable to any system with GNU find, you mean (the -mmin test isn't
> standard).  It also assumes the filename is not just one or more newline
> characters, but that might be getting a little bit too pedantic.

You are correct, the "-mmin" predicate is not standard, that was
me being careless.  Although it _is_ supported in other find
implementations than GNU find.

For the other issue, one could use "-exec echo x \;" instead of
"-print", or anything that outputs something that isn't stripped off by
the command substitution (maybe "-ls" if that's implemented).

However, it looks a bit awkward to do this on a single file.  It wasn't
stated in the question what the workflow looks like, but if something is
to be done to _all_ files older/newer than an hour, this would probably
be better done through "find ... -mmin +60 -exec ... {} +". But that's
not really related to bash.

... or one could use a zsh glob with a "(mh+1)" glob qualifier...


-- 
Kusalananda
Sweden