2010-04-18 07:06:40

by ratheesh kannoth

[permalink] [raw]
Subject: open sockets from task_struct

I have task_struct structure , how to find all the opened files ? how
to find opened sockets ?

Thanks,
Ratheesh


2010-04-18 07:30:47

by Jonathan Campbell

[permalink] [raw]
Subject: Re: open sockets from task_struct

(reposted because I remember kernel.org mentioning that HTML email is
verboten or something like that---Sorry!)

I know that on the user-space side any open handles can be seen in the
/proc/<pid>/fd directory (<pid> is whatever process you're interested in).
Assuming you're talking about reading this from kernel space, I'd look
at what the procfs filesystem is doing and learn from that.
Sockets and block/char devices are listed like any other file, the list
is based on file handles.

> I have task_struct structure , how to find all the opened files ? how
> to find opened sockets ?
>
> Thanks,
> Ratheesh
> --
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>

2010-04-18 08:12:30

by Jonathan Campbell

[permalink] [raw]
Subject: Re: open sockets from task_struct

Get the Linux kernel source and look at what the procfs filesystem is
doing to get that information. Look under fs/proc.
fs/proc/base.c(2508) seems to contain the inode structures for
/proc/pid/fd and /proc/pid/fdinfo, locate the inode operations
structure and locate the functions. Drill down through the function
calls and you'll eventually find how to read what
file handles are open. A quick glance tells me that the calls go several
layers deep including a call through a function pointer passed in one of
the parameters, "instantiate", hopefully that won't be a problem for you.
> On Sun, Apr 18, 2010 at 12:53 PM, Jonathan Campbell<[email protected]> wrote:
>
>> I know that on the user-space side any open handles can be seen in the
>> /proc/<pid>/fd directory (<pid> is whatever process you're interested in).
>> Assuming you're talking about reading this from kernel space, I'd look at
>> what the procfs filesystem is doing and learn from that.
>> Sockets and block/char devices are listed like any other file, the list is
>> based on file handles.
>>
>>> I have task_struct structure , how to find all the opened files ? how
>>> to find opened sockets ?
>>>
>>> Thanks,
>>> Ratheesh
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>>> the body of a message to [email protected]
>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>> Please read the FAQ at http://www.tux.org/lkml/
>>>
>>>
>>>
>>>
>>
>>
> I need it in kernel space and i am using 2.6.29.4 kernel .. could you
> please guide a little ?
>
>
>