On Wed, May 28, 2008 at 6:45 PM, Manish Katiyar <[EMAIL PROTECTED]> wrote:
> On Wed, May 28, 2008 at 5:55 PM, Prasad Joshi <[EMAIL PROTECTED]>
> wrote:
> > Yes, I read the code
> >
> > On Wed, May 28, 2008 at 5:44 PM, Manish Katiyar <[EMAIL PROTECTED]>
> wrote:
> >>
> >> On Wed, May 28, 2008 at 5:43 PM, Manish Katiyar <[EMAIL PROTECTED]>
> >> wrote:
> >> > On Wed, May 28, 2008 at 5:06 PM, Prasad Joshi <
> [EMAIL PROTECTED]>
> >> > 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
>
> How does this come to 2 then ?
>
> 11 40700 (2) 0 0 12288 27-May-2008 20:02 lost+found
>
> Since it is a directory, the link count should be minimum 2.
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 <[EMAIL PROTECTED]
> >
> >> >> wrote:
> >> >>>
> >> >>> On Wed, May 28, 2008 at 12:17 AM, Frédéric Weisbecker
> >> >>> <[EMAIL PROTECTED]> 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 <[EMAIL PROTECTED]>:
> >> >>> >>
> >> >>> >> 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
> ***********************************************
>
