Question regarding FLOCK or POSIX with Sendmail 8.13.x and MailScanner.

David Lee t.d.lee at
Thu Nov 2 10:07:20 GMT 2006

On Wed, 1 Nov 2006, Duncan, Brian M. wrote:

> > That default changed in 4.50.15-1. Are you running something older?
> > Does MailScanner -V work?
> >
> Yes here is the output from one of my sendmail-8.13.8-1/MailScanner
> 4.54.6-1 boxes:
> Does anything look off?

Yes, I think there is a problem...

> [...]
> This is MailScanner version 4.54.6
> [...]

Earlier this year, there was an internal inconsistency within MS which I
spotted at 4.54.6 .

In "MailScanner.conf" the comments describing the default "Lock Type"
(i.e. left blank) behaviour said 'it defaults to "posix"', but the actual
behaviour (when left blank) was to set it to "flock".

That is, the comments said MS would behave one way but its actual
behaviour was the opposite.

See threads starting at:
and Julian's acknowledgement and fix at:

So either upgrade to a more recent version (than 4.54.6) or if you need to
stay back at 4.54.6 then explicitly state which lock type you want.

Hope that helps.


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