Subject Re: [Firebird-Java] Java and embedded Firebird
Author Roman Rokytskyy
> I am confused with the following notes in README_embedded.txt of embed
> distribution. Does it mean that it is possible for multiple JVMs to do
> queries from a same database (e.g. one of the JVM would host as a
> embedded server and the other JVMs to connect to it)?

No, it is not possible. On Windows you will get an error message when
connecting to the database (FB embedded locks the database file
exclusively), on UNIXes you will get no error on connection, but you
_will_ corrupt your database if two processes access it simultaneously
(unfortunately there is no exclusive file lock in POSIX, so different VMs
will write different data on the same database pages, etc.).

So, if you want to have multiple JVMs accessing same database file, you
have to install FB server. Then you can either use IPC (via shared memory)
or TCP/IP connection. Running embedded server within a JVM won't provide
you IPC server capabilities.