[TriLUG] How reliable is inotifywait?

[James Toebes via TriLUG]

Had not seen that feature of SystemD.  Will need to investigate it more.

On 3/11/24 18:32, Scott Lambdin wrote:
> Interesting.  I saw a web page called "Replacing incron with 
> systemd."  Looks like there may be a new way to do it.  I can't get to 
> the page, perhaps because I am at a cigar bar in Mexico.
>
> On Mon, Mar 11, 2024, 4:06 PM Scott Lambdin <lopaki at gmail.com> wrote:
>
>     iNotify/incron has been around like ten years.  If you can find an
>     active incron message board, that would probably be a good place
>     to look for failure reports.
>
>     On Sun, Mar 10, 2024, 5:24 PM James Toebes via TriLUG
>     <trilug at trilug.org> wrote:
>
>         Have you checked out incron?   Similar to cron,  but runs on
>         inodes.
>         You can easily define script that run when a file is added,
>         deleted....
>
>
>         On 3/10/24 18:41, Ken VanDine via TriLUG wrote:
>         > In my experience it's very reliable.  We use it in Ubuntu to
>         determine when
>         > the display server is up before starting the installer.
>         >
>         >
>         https://github.com/canonical/ubuntu-core-desktop-installer/blob/00cb18b0b2512bb81986c6259d5561fc5a9e3976/launcher/launcher#L57
>         >
>         > Cheers,
>         > Ken
>         >
>         >
>         > On Sun, Mar 10, 2024, 6:09 PM Steve Litt via TriLUG
>         <trilug at trilug.org>
>         > wrote:
>         >
>         >> Hi all,
>         >>
>         >> The inotifywait program waits until a specific file event
>         happens in a
>         >> specific directory or file, and then terminates. So it enables
>         >> file-driven event driven programs.
>         >>
>         >> I'd like to wake up the instant a file appears in a directory.
>         >> Something like the following:
>         >>
>         >> inotifywait -e create -e moved_to -t 30 /tmp/pager
>         >>
>         >> The preceding waits 30 seconds, except if a file is created
>         in or moved
>         >> to /tmp/pager, it quits waiting and terminates immediately.
>         >>
>         >> I use it to combine polling with an event driven, so if for
>         some reason
>         >> the event (moved_to or create) doesn't quit and terminate
>         immediately,
>         >> it will still quit and terminate at the end of 30 seconds.
>         >>
>         >> I can significantly simplify my program if I changed -t 30
>         to t -1,
>         >> where -1 stands for "forever". False positives aren't a
>         problem: They
>         >> would just start another cycle. But false negatives, where
>         a file is
>         >> created or moved into /tmp/pager but fails to quit and
>         terminate, would
>         >> really mess me up in this particular situation.
>         >>
>         >> So what do you think, is inotifywait reliable?
>         >>
>         >> Thanks,
>         >>
>         >> SteveT
>         >>
>         >> Steve Litt
>         >>
>         >> Autumn 2023 featured book: Rapid Learning for the 21st Century
>         >> http://www.troubleshooters.com/rl21
>         >> --
>         >> This message was sent to: Ken VanDine <ken at vandine.org>
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>         -- 
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