Chris,

Unioned filesystems are a fundamental design of QNX Neutrino.  Take a
look at the rsrcdbmgr_* calls. Several resource managers use this API to
ensure only a single copy is running at a time.

David

> -----Original Message-----
> From: Chris Trobridge [mailto:community-noreply@qnx.com]
> Sent: July-25-11 10:24 AM
> To: ostech-core_os
> Subject: Resource Manager Path Management
> 
> My initial assumption was that you could only have one resource
manager
> 'registered' at a particular point in the file system.
> 
> Experience and closer reading of the docs suggests that it's possible
> to have more than one resource manager registered to the same path.
> 
> I can see that this has uses but how do you ensure that you only
create
> one instance of a driver? (assuming that there's potentially a race
> between different processes to create one)
> 
> There's no global mutex available so would you just design the system
> to avoid potential race conditions associated with driver creation?
> 
> 
> 
> 
> 
> _______________________________________________
> 
> OSTech
> http://community.qnx.com/sf/go/post87571