Il lun 8 mag 2017, 18:38 Remi Forax <fo...@univ-mlv.fr> ha scritto: > > > ----- Mail original ----- > > De: "Roger Riggs" <roger.ri...@oracle.com> > > À: core-libs-dev@openjdk.java.net > > Envoyé: Lundi 8 Mai 2017 17:45:25 > > Objet: Re: Accessing UNIX FileDescriptor id without reflection > > > 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. >
I like this option. I will give it a try. Thank you all very much Enrico > s/Rémi/Peter > Peter is right, i'm wrong :) > > > > > Roger > > Rémi > > > > > > > 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 > -- -- Enrico Olivelli
