[OpenAFS-devel] enhance audit logs to support Sys V message queues

[Steven Jenkins]

On Wed, Apr 22, 2009 at 9:20 PM, Russ Allbery <rra@stanford.edu> wrote:
> Steven Jenkins <steven.jenkins@gmail.com> writes:
>
>> I just uploaded a preliminary patch to openafs-bugs (RT #124674) that
>> adds support to audit logs for Sys V message queues. =A0In other words,
>> if you run this patch, instead of audit logs going to a file, they can
>> go to Sys V message queues. =A0There is an additional option to
>> configure if you want to experiment with this: --with-audit-interface,
>> with two options: file and sysvmq, defaulting to file.
>
> Out of curiosity, what do you get from message queues that you don't get
> from a named pipe? =A0No blocking if you have no reader?
>

You can choose to do non-blocking for named pipes.   However, named
pipes (aka 'FIFO's to many in the Linux world) have a much tighter
coupling between producers and consumers than message queues do.  For
example, if a writer tries to write to a named pipe that  has no
readers, a SIGPIPE (or EPIPE if SIGPIPE is being ignored) is
generated.

--=20
Steven Jenkins
End Point Corporation
http://www.endpoint.com/