This topic is discussed at length in the "Safe ways to lock a database section" of the latest DB_File docs. A small excerpt:

Safe ways to lock a database

Starting with version 2.x, Berkeley DB  has internal 
support for locking.  The companion module to this one,
BerkeleyDB, provides an interface to this locking 
functionality. If you are serious about locking Berkeley 
DB databases, I strongly recommend using BerkeleyDB.

If using BerkeleyDB isn't an option, there are a number 
of modules available on CPAN that can be used to implement
locking.

The docs name these modules, as well as some alternative locking schemes. Good luck !

In reply to Re: File rights? by kschwab
in thread File rights? by HDrider

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