On Wed, May 28, 2008 at 6:45 PM, Manish Katiyar <mkatiyar@xxxxxxxxx> wrote:
This is the code which is doing the printing
fprintf(ls->f, "%c%6u%c %6o (%d) %5d %5d ", lbr, ino, rbr,
inode.i_mode, dirent->name_len >> 8,
inode_uid(inode), inode_gid(inode));
It is not link count. If you see test file has 3 links test, test1, and test3. So, the number in the Bracket is not the link count
debugfs: stat test
Inode: 12 Type: regular Mode: 0644 Flags: 0x0 Generation: 3442830008
User: 0 Group: 0 Size: 1037
File ACL: 338 Directory ACL: 0
Links: 3 Blockcount: 6
Fragment: Address: 0 Number: 0 Size: 0
ctime: 0x483d4909 -- Wed May 28 17:29:05 2008
atime: 0x483d496e -- Wed May 28 17:30:46 2008
mtime: 0x483c1c18 -- Tue May 27 20:05:04 2008
BLOCKS:
(0-1):7169-7170
TOTAL: 2
debugfs: ls -l
2 40755 (2) 0 0 1024 27-May-2008 20:03 .
2 40755 (2) 0 0 1024 27-May-2008 20:03 ..
11 40700 (2) 0 0 12288 27-May-2008 20:02 lost+found
12 100644 (1) 0 0 1037 27-May-2008 20:05 test
13 40755 (2) 0 0 2048 27-May-2008 20:08 dir
12 100644 (1) 0 0 1037 27-May-2008 20:05 test1
12 100644 (1) 0 0 1037 27-May-2008 20:05 test2
How does this come to 2 then ?On Wed, May 28, 2008 at 5:55 PM, Prasad Joshi <prasadjoshi124@xxxxxxxxx> wrote:
> Yes, I read the code
>
> On Wed, May 28, 2008 at 5:44 PM, Manish Katiyar <mkatiyar@xxxxxxxxx> wrote:
>>
>> On Wed, May 28, 2008 at 5:43 PM, Manish Katiyar <mkatiyar@xxxxxxxxx>
>> wrote:
>> > On Wed, May 28, 2008 at 5:06 PM, Prasad Joshi <prasadjoshi124@xxxxxxxxx>
>> > wrote:
>> >> Thanks a lot for all the replies.
>> >>
>> >> I am able to use the debugfs. But, I am not able to understand the
>> >> information displayed by ls -l command in the debugfs env
>> >> Here, is a sample output
>> >>
>> >> This is the current directory structure (file system is mounted at
>> >> /mnt)
>> >> /mnt/
>> >> |--------------- dir
>> >> | |----------------- 1
>> >> |--------------- lost+found
>> >> |--------------- test
>> >> |--------------- test1
>> >> |--------------- test2
>> >>
>> >> test1 and test2 are hard links to file test (there is no data in the
>> >> file)
>> >>
>> >> HERE IS THE OUTPUT
>> >>
>> >> debugfs: ls -l
>> >> 2 40755 (2) 0 0 1024 27-May-2008 20:03 .
>> >> 2 40755 (2) 0 0 1024 27-May-2008 20:03 ..
>> >> 11 40700 (2) 0 0 12288 27-May-2008 20:02 lost+found
>> >> 12 100644 (1) 0 0 1037 27-May-2008 20:05 test
>> >> 13 40755 (2) 0 0 2048 27-May-2008 20:08 dir
>> >> 12 100644 (1) 0 0 1037 27-May-2008 20:05 test1
>> >> 12 100644 (1) 0 0 1037 27-May-2008 20:05 test2
>> >>
>> >> debugfs: ls -l dir
>> >> 13 40755 (2) 0 0 2048 27-May-2008 20:08 .
>> >> 2 40755 (2) 0 0 1024 27-May-2008 20:03 ..
>> >> 14 40755 (2) 0 0 1024 28-May-2008 15:48 1
>> >> 0 0 (0) 0 0 0
>> >>
>> >> debugfs: ls -l dir/1
>> >> 14 40755 (2) 0 0 1024 28-May-2008 15:48 .
>> >> 13 40755 (2) 0 0 2048 27-May-2008 20:08 ..
>> >>
>> >> debugfs: mkdir dir/2
>> >> debugfs: ls -l
>> >> 2 40755 (2) 0 0 1024 27-May-2008 20:03 .
>> >> 2 40755 (2) 0 0 1024 27-May-2008 20:03 ..
>> >> 11 40700 (2) 0 0 12288 27-May-2008 20:02 lost+found
>> >> 12 100644 (1) 0 0 1037 27-May-2008 20:05 test
>> >> 13 40755 (2) 0 0 2048 27-May-2008 20:08 dir
>> >> 12 100644 (1) 0 0 1037 27-May-2008 20:05 test1
>> >> 12 100644 (1) 0 0 1037 27-May-2008 20:05 test2
>> >>
>> >> debugfs: ls -l dir
>> >> 13 40755 (2) 0 0 2048 27-May-2008 20:08 .
>> >> 2 40755 (2) 0 0 1024 27-May-2008 20:03 ..
>> >> 14 40755 (2) 0 0 1024 28-May-2008 15:48 1
>> >> 15 40755 (2) 0 0 1024 28-May-2008 16:51 2
>> >> 0 0 (0) 0 0 0
>> >>
>> >> Can any one please tell me what these collumns represent?
>> >
>> > It appears you are using debugfs from e2fsprogs. The columns seem to be
>> >
>> > 1) inode number
>> > 2) permissons/mode,
>> > 3) From the code it is "dirent->name_len >> 8", but my guess is it is
>> > number of links.
>> > 4) uid
>> > 5) gid
>> 6) There is size too :-)
>> > 6) datetime string
>> > 7) file name.
>> >
>> >
>> > Hope that helps.
>
> Yes correct, I also went through the code of e2fsprogs. File for ls code is
> debugfs/ls.c
> 1. Inode Number
> 2. Inode Mode.
> 3. dirent->name_len >> 8 it is lenght in bytes
Since it is a directory, the link count should be minimum 2.
11 40700 (2) 0 0 12288 27-May-2008 20:02 lost+found
This is the code which is doing the printing
fprintf(ls->f, "%c%6u%c %6o (%d) %5d %5d ", lbr, ino, rbr,
inode.i_mode, dirent->name_len >> 8,
inode_uid(inode), inode_gid(inode));
It is not link count. If you see test file has 3 links test, test1, and test3. So, the number in the Bracket is not the link count
debugfs: stat test
Inode: 12 Type: regular Mode: 0644 Flags: 0x0 Generation: 3442830008
User: 0 Group: 0 Size: 1037
File ACL: 338 Directory ACL: 0
Links: 3 Blockcount: 6
Fragment: Address: 0 Number: 0 Size: 0
ctime: 0x483d4909 -- Wed May 28 17:29:05 2008
atime: 0x483d496e -- Wed May 28 17:30:46 2008
mtime: 0x483c1c18 -- Tue May 27 20:05:04 2008
BLOCKS:
(0-1):7169-7170
TOTAL: 2
debugfs: ls -l
2 40755 (2) 0 0 1024 27-May-2008 20:03 .
2 40755 (2) 0 0 1024 27-May-2008 20:03 ..
11 40700 (2) 0 0 12288 27-May-2008 20:02 lost+found
12 100644 (1) 0 0 1037 27-May-2008 20:05 test
13 40755 (2) 0 0 2048 27-May-2008 20:08 dir
12 100644 (1) 0 0 1037 27-May-2008 20:05 test1
12 100644 (1) 0 0 1037 27-May-2008 20:05 test2
--
> 4. UID
> 5. GID
> 6. Date
> 7. File Name
>
> Thanks a lot for your reply.
> --Prasad.
>
>>
>> >
>> >
>> >>
>> >> Thanks and Regards,
>> >> Prasad.
>> >>
>> >> On Wed, May 28, 2008 at 8:00 AM, Peter Teoh <htmldeveloper@xxxxxxxxx>
>> >> wrote:
>> >>>
>> >>> On Wed, May 28, 2008 at 12:17 AM, Frédéric Weisbecker
>> >>> <f.weisbecker@xxxxxxxxx> wrote:
>> >>> > Hi!
>> >>> >
>> >>> > Here is a small tutorial:
>> >>> >
>> >>> >
>> >>> > http://docs.blackfin.uclinux.org/doku.php?id=file_systems#file_system_exampledebugfs
>> >>>
>> >>> Yes, that is the kernel-based debugfs, and u used it via the following
>> >>> manner (not mentioned in the page, but widely available in Internet):
>> >>>
>> >>> Method 1:
>> >>>
>> >>> put the following line in /etc/fstab for automatic moutning at bootup:
>> >>>
>> >>> none /sys/kernel/debug debugfs
>> >>> defaults 0 0
>> >>>
>> >>>
>> >>> Method 2:
>> >>>
>> >>> Issue:
>> >>>
>> >>> mount -t debugfs none /sys/kernel/debug
>> >>>
>> >>> at command line level.
>> >>>
>> >>> BUT....in my Fedora FC7 distros, at the commandline level there is a
>> >>> "debugfs" command (man debugfs):
>> >>>
>> >>> DEBUGFS(8)
>> >>> DEBUGFS(8)
>> >>>
>> >>> NAME
>> >>> debugfs - ext2/ext3 file system debugger
>> >>>
>> >>> SYNOPSIS
>> >>> debugfs [ -Vwci ] [ -b blocksize ] [ -s superblock ] [ -f
>> >>> cmd_file
>> >>> ] [
>> >>> -R request ] [ -d data_source_device ] [ device ]
>> >>>
>> >>> DESCRIPTION
>> >>> The debugfs program is an interactive file system debugger. It
>> >>> can
>> >>> be
>> >>> used to examine and change the state of an ext2 file system.
>> >>> device is the special file corresponding to the device
>> >>> containing
>> >>> the
>> >>> ext2 file system (e.g /dev/hdXX).
>> >>>
>> >>> OPTIONS
>> >>> -w Specifies that the file system should be opened in
>> >>> read-write
>> >>> mode. Without this option, the file system is opened
>> >>> in
>> >>> read-
>> >>> only mode.
>> >>>
>> >>> .........
>> >>>
>> >>> Very confusing.....but I think this is not what u want....it is a tool
>> >>> as part of the e2fsprogs package (e2fsprogs.sourceforge.net, I think).
>> >>>
>> >>>
>> >>> > If you need more help to use it, don't hesitate to ask!
>> >>> > As you will see there are two ways to use it:
>> >>> >
>> >>> > _ By creating a file which exports or import a single variable. It's
>> >>> > simple
>> >>> > but asynchronous (you or the user-process needs to check
>> >>> > periodically if
>> >>> > the
>> >>> > value has changed.
>> >>> > _ By implementing the common file operations. But it stays simple
>> >>> > and
>> >>> > it's
>> >>> > synchronous.
>> >>> >
>> >>> > Regards,
>> >>> > Frédéric...
>> >>> >
>> >>> >
>> >>> >
>> >>> >
>> >>> > 2008/5/27 Prasad Joshi <prasadjoshi124@xxxxxxxxx>:
>> >>> >>
>> >>> >> Hi All,
>> >>> >>
>> >>> >> I have an assignment and I am supposed to use debugfs for the same.
>> >>> >> Can anyone please help me? or Point me to a link which tells how
>> >>> >> to
>> >>> >> use
>> >>> >> debug fs?
>> >>> >>
>> >>> >> Thanks and Regards,
>> >>> >> Prasad
>> >>> >
>> >>> >
>> >>>
>> >>>
>> >>>
>> >>> --
>> >>> Regards,
>> >>> Peter Teoh
>> >>
>> >>
>> >
>> >
>> >
>> > --
>> > Thanks & Regards,
>> > ********************************************
>> > Manish Katiyar ( http://mkatiyar.googlepages.com )
>> > 3rd Floor, Fair Winds Block
>> > EGL Software Park
>> > Off Intermediate Ring Road
>> > Bangalore 560071, India
>> > ***********************************************
>> >
>>
>>
>>
>> --
>> Thanks & Regards,
>> ********************************************
>> Manish Katiyar ( http://mkatiyar.googlepages.com )
>> 3rd Floor, Fair Winds Block
>> EGL Software Park
>> Off Intermediate Ring Road
>> Bangalore 560071, India
>> ***********************************************
>
>
Thanks & Regards,
********************************************
Manish Katiyar ( http://mkatiyar.googlepages.com )
3rd Floor, Fair Winds Block
EGL Software Park
Off Intermediate Ring Road
Bangalore 560071, India
***********************************************
