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Article #62Re: File.lengh() return 0 while the file's length > 0 on Linux
From: Kevin Dean [TeamB]
Date: Thu, 17 Mar 2005 16:28
Date: Thu, 17 Mar 2005 16:28
39 lines
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2297 bytes
Chris wrote:
> When using File.length to get the size of a file on linux, it returns
> 0; but I am sure the file has contents, Could someone give me a hint?
>
> Thanks in advance .
>
> //test.java
> import java.io.*;
> public class test
> {
> public static void main(String args[])
> {
> File file = new File("/proc/mdstat");
> System.out.println("file.length(): " + file.length());
> }
> }
The /proc filesystem is a special file system that maintains process
state. The contents don't exist on disk but rather in memory, and the
contents are highly dynamic. Because you're not opening a real file
per se, there's no easy way to determine the length, so Java returns 0.
Details on /proc can be found here:
http://www.freeos.com/articles/2879/
--
Kevin Dean [TeamB]
Dolphin Data Development Ltd.
http://www.datadevelopment.com/
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From: "Kevin Dean [TeamB]" <NkOdSePaAnM@datadevelopment.com>
Subject: Re: File.lengh() return 0 while the file's length > 0 on Linux
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