Path: csiph.com!x330-a1.tempe.blueboxinc.net!newsfeed.hal-mli.net!feeder3.hal-mli.net!newsfeed.hal-mli.net!feeder1.hal-mli.net!nx01.iad01.newshosting.com!newshosting.com!69.16.185.11.MISMATCH!npeer01.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail
From: Lew <lewbloch@gmail.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: java.io.File
Date: Fri, 2 Dec 2011 14:07:57 -0800 (PST)
Organization: http://groups.google.com
Lines: 29
Message-ID: <3749375.667.1322863677698.JavaMail.geo-discussion-forums@preu18>
References: <lt6hd7h1agr1kb9vud97fpabja00p0pbtn@4ax.com> <1754083.312.1322839502470.JavaMail.geo-discussion-forums@prjr26> <4ed8fc62$0$10730$426a74cc@news.free.fr>
Reply-To: comp.lang.java.programmer@googlegroups.com
NNTP-Posting-Host: 2620:0:1000:fd2b:224:d7ff:fe69:5838
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
X-Trace: posting.google.com 1322863677 21762 127.0.0.1 (2 Dec 2011 22:07:57 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Fri, 2 Dec 2011 22:07:57 +0000 (UTC)
In-Reply-To: <4ed8fc62$0$10730$426a74cc@news.free.fr>
Complaints-To: groups-abuse@google.com
Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=2620:0:1000:fd2b:224:d7ff:fe69:5838; posting-account=CP-lKQoAAAAGtB5diOuGlDQk0jIwmH0T
User-Agent: G2/1.0
X-Google-Web-Client: true
Xref: x330-a1.tempe.blueboxinc.net comp.lang.java.programmer:10438

Mayeul wrote:
>Lew wrote:
>> Mark wrote:
>>> Can a java.io.File object use a OS file descriptor?  I am trying to
>>> find the source of a fd leak in a[n] application.
>>
>> At some point, depending on the operations performed by the 'File' insta=
nce, there may be a file descriptor involved, and then the 'File' instance =
certainly does use it, at least indirectly via JVM system calls that proxy =
to OS system calls.
>=20
> It was my understanding that java.io.File instances were merely=20
> representations of pathnames, and are neither closed nor opened, just=20
> places and names where files could exist or not.

How, then, do calls like 'File#canRead()', 'canWrite()', 'createNewFile()',=
 'createTempFile()', 'delete()', 'exists()', 'getFreeSpace()', 'isDirectory=
()', 'isFile()', 'list()', 'listFiles()', 'mkdir()', 'mkdirs()', 'setReadab=
le()', 'setReadOnly()' and 'setWritable()' work?

> It was also my understanding that file descriptors were representations=
=20
> of opened files.

Maybe those operations don't use file descriptors, but they do use OS files=
ystem resources.

--=20
Lew