Re: File Locking Question

Roedy Green wrote:


Which says:

#Starting with Java 1.4, there is the java.nio.channels. FileLock class.
#The locking is confined to a single JVM. Non-Java apps or Java running
#in other JVMs won't see it.

But some people may prefer to believe what the Java Doc says:

#Platform dependencies
#
#This file-locking API is intended to map directly to the native
#locking facility of the underlying operating system. Thus the locks
#held on a file should be visible to all programs that have access to
#the file, regardless of the language in which those programs are
#written.
#
#Whether or not a lock actually prevents another program from
#accessing the content of the locked region is system-dependent and
#therefore unspecified. The native file-locking facilities of some
#systems are merely advisory, meaning that programs must cooperatively
#observe a known locking protocol in order to guarantee data integrity.
#On other systems native file locks are mandatory, meaning that if one
#program locks a region of a file then other programs are actually
#prevented from accessing that region in a way that would violate the
#lock. On yet other systems, whether native file locks are advisory or
#mandatory is configurable on a per-file basis. To ensure consistent and
#correct behavior across platforms, it is strongly recommended that the
#locks provided by this API be used as if they were advisory locks.

Arne