Re: locking files on Linux

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Date	Thu, 18 Oct 2012 14:44:27 +0100
Subject	Re: locking files on Linux
From	andrea crotti <andrea.crotti.0@gmail.com>
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2012/10/18 Grant Edwards <invalid@invalid.invalid>:
> On 2012-10-18, andrea crotti <andrea.crotti.0@gmail.com> wrote:
>
>
> File locks under Unix have historically been "advisory".  That means
> that programs have to _choose_ to pay attention to them.  Most
> programs do not.
>
> Linux does support mandatory locking, but it's rarely used and must be
> manually enabled at the filesystem level. It's probably worth noting
> that in the Linux kernel docs, the document on mandatory file locking
> begins with a section titled "Why you should avoid mandatory locking".
>
> http://en.wikipedia.org/wiki/File_locking#In_Unix-like_systems
> http://kernel.org/doc/Documentation/filesystems/locks.txt
> http://kernel.org/doc/Documentation/filesystems/mandatory-locking.txt
> http://www.thegeekstuff.com/2012/04/linux-file-locking-types/
> http://www.hackinglinuxexposed.com/articles/20030623.html
>
> --
> Grant Edwards               grant.b.edwards        Yow! Your CHEEKS sit like
>                                   at               twin NECTARINES above
>                               gmail.com            a MOUTH that knows no
>                                                    BOUNDS --
> --
> http://mail.python.org/mailman/listinfo/python-list


Uhh I see thanks, I guess I'll use the good-old .lock file (even if it
might have some problems too).

Anyway I'm only afraid that my same application could modify the
files, so maybe I can instruct it to check if the file is locked.

Or maybe using sqlite would work even if writing from different
processes?

I would prefer to keep something human readable as INI-format though,
rather then a sqlite file..

Thanks

Thread

locking files on Linux andrea crotti <andrea.crotti.0@gmail.com> - 2012-10-18 14:14 +0100
  Re: locking files on Linux Grant Edwards <invalid@invalid.invalid> - 2012-10-18 13:27 +0000
    Re: locking files on Linux andrea crotti <andrea.crotti.0@gmail.com> - 2012-10-18 14:44 +0100
      Re: locking files on Linux Grant Edwards <invalid@invalid.invalid> - 2012-10-18 13:57 +0000
        Re: locking files on Linux andrea crotti <andrea.crotti.0@gmail.com> - 2012-10-18 15:49 +0100
        Re: locking files on Linux Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2012-10-18 16:04 +0100
        Re: locking files on Linux andrea crotti <andrea.crotti.0@gmail.com> - 2012-10-18 16:08 +0100
        Re: locking files on Linux Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2012-10-18 16:31 +0100
        Re: locking files on Linux andrea crotti <andrea.crotti.0@gmail.com> - 2012-10-19 13:15 +0100
      Re: locking files on Linux Nobody <nobody@nowhere.com> - 2012-10-19 15:36 +0100
    Re: locking files on Linux Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2012-10-18 14:58 +0100

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