From mboxrd@z Thu Jan  1 00:00:00 1970
From: fruktopus@gmail.com (=?UTF-8?B?U3RlcGhhbiBNw7xsbGVy?=)
Date: Fri, 26 Jun 2015 10:00:03 +0200
Subject: Filesize in sysfs, debugfs, ...
Message-ID: <558D0683.8080205@gmail.com>
To: kernelnewbies@lists.kernelnewbies.org
List-Id: kernelnewbies.lists.kernelnewbies.org

Hi all, 

I have a question, what is the policy on file size in sysfs and especially in debugfs?

Many (but not all) of the files report a size of 0. Recently I diffed against a file in sysfs. The files were identical, despite the fact one reported size 0. I got the unpleasant result

diff -as file1 file2                (treat both as text, report identical files)
Files file1 and file2 are identical

diff -asq file1 file2               (treat both as text, report just yes/no)
Files file1 and file2 differ

In brief mode diff looks first for file sizes and stops if they don't match. 

For files which don't differ in size (e.q, exposing a bool) it would be easy to set the proper size for others it's not.


   Thank you,
   Stephan