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From: "Morten Kjærulff" <mortenkjarulff@gmail.com>
To: cygwin@cygwin.com
Subject: Re: find command seems to lock files
Date: Mon, 19 Aug 2019 14:41:00 -0000	[thread overview]
Message-ID: <CA+7cx1rZyYwdeGSJFKdzvw_Rjm_4shVY+B-3c0DJmBcqXvjuNA@mail.gmail.com> (raw)
In-Reply-To: <20190819141321.GO11632@calimero.vinschen.de>

On Mon, Aug 19, 2019 at 4:13 PM Corinna Vinschen
<corinna-cygwin@cygwin.com> wrote:
>
> On Aug 19 10:06, Eliot Moss wrote:
> > On 8/19/2019 10:03 AM, Corinna Vinschen wrote:
> > > On Aug 19 14:33, Morten Kjærulff wrote:
> > > > Hi,
> > > >
> > > > I have an application which constantly:
> > > > creates a file
> > > > do some processing
> > > > deletes the file
> > > >
> > > > One way to monitor if the application has crashed, is to check the age of
> > > > the file, so I made a script that:
> > > >
> > > > find //$server/d$/dir/subdir*/subsubdir -name 'thefile' -printf '%A+\n'
> > > >
> > > > subdir* will be subdir1 subdir2 ...
> > > > under subsubdir there will be dirA, dirB, ... and under those, thefile may
> > > > exist.
> > > >
> > > > Problem is that it seems this command locks thefile, as the application
> > > > sometimes can't delete it.
> > > >
> > > > Could this be true?
> > >
> > > Cygwin does not actually lock anything except in very rare
> > > circumstances.  Your problem is more likely triggered by a realtime
> > > virus scanner.
> >
> > I was wondering, though, whether the parent directory would
> > be non-delete-able while find has the directory open for scanning.
>
> Usually yes.  Cygwin moves the entire directory into the recycler in
> case it's a local dir.  That works even if a file is blocking the
> dir from deletion.
>
> > If the application in question creates and deletes the parent
> > directory, as well as the leaf file, then things would be left
> > around unexpectedly.
>
> The question was just if the file is locked.
>
> > So would use of find trigger a virus scanner, which in turn might
> > hold on to the file and prevent its deletion?
>
> That's how some realtime scanners work.  They have hooks in the file API
> and if some other process opens a file these scanners open the file as
> well, typically without FILE_SHARE_DELETE, which Cygwin uses by default.
>
>
> Corinna
>
> --
> Corinna Vinschen
> Cygwin Maintainer

I forgot to say that I run the find command on my own PC, and the
application runs on a server, which I have 'net use' its disk.

Would it be the virus scanner on my PC or on the server?
Any idea of a different way to get the age of the file? (I am sure I
cannot change the virus scanner).

/Morten

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  reply	other threads:[~2019-08-19 14:26 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-19 12:49 Morten Kjærulff
2019-08-19 14:06 ` Corinna Vinschen
2019-08-19 14:13   ` Eliot Moss
2019-08-19 14:26     ` Corinna Vinschen
2019-08-19 14:41       ` Morten Kjærulff [this message]
2019-08-19 15:03         ` Eliot Moss
2019-08-19 17:05         ` Andrey Repin
2019-08-19 17:21           ` Andrey Repin
2019-08-19 17:41           ` Morten Kjærulff
2019-08-19 18:52             ` Eliot Moss
2019-08-19 19:43           ` Greywolf
2019-08-21 19:53           ` L A Walsh
2019-08-26  1:57 ` Chris Wagner

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