Hi,
I would be very cautious about giving out fds for arbitrary FileDescriptors.
With concurrency and threading, how do you make sure that it does not
not get closed
and someone's code still has the fd and uses it later? Or worse yet,
the fd gets re-used
and then it is possible to operate on the wrong file.
Quite a bit of implementation code assumes it has complete control over
the lifecycle of
the FileDescriptor. Exposing the raw FD breaks the encapsulation.
As Rémi suggests, passing the FileDescriptor to native will at least
maintain the current
encapsulation.
Roger
On 5/8/2017 10:14 AM, Remi Forax wrote:
I agree that a method getFd should be great, we will need this kind of value if
we want to use Panama.
Did you try to serializing the FileDescriptor in memory and extract the int
corresponding to the file descriptor ?
cheers,
Rémi
----- Mail original -----
De: "Enrico Olivelli" <eolive...@gmail.com>
À: core-libs-dev@openjdk.java.net
Envoyé: Lundi 8 Mai 2017 15:16:24
Objet: Accessing UNIX FileDescriptor id without reflection
Hi,
I am trying to port a project (Apache BookKeeper) to Java9, actually
this code uses reflection in order to access the 'fd' field of the
FileDescriptor class.
We have to access that ID in order to call low level native functions
See
https://github.com/apache/bookkeeper/blob/master/bookkeeper-server/src/main/java/org/apache/bookkeeper/util/NativeIO.java
# getSysFileDescriptor
Is there any way to access the FD handle without using reflection ?
If not, is it possibile to enhance the FileDescriptor API in order to
given access to the internal "fd" field ?
Thank you
Enrico Olivelli
