System Call

From: Koushik Chakraborty (kchak@iitk.ac.in)
Date: Sat Jan 29 2000 - 04:06:11 EST


Hi,
  I am trying to build a new system call which needs to perform a 'read'
on a TCP socket. Now when we call read , the system call goes through
sock_read,sock_recvmsg etc .. through to tcp_recvmsg where the data is
actually copied in another function called by tcp_recvmsg ..
memcpy_toiovec. However, in this special case I need the "memcpy_toiovec"
to perform in a slightly different manner. However, all along these calls
no actor is taken as argument so tcp_recvmsg will always call
memcpy_toiovec. I tried to pass a negative "count" paramter during calling
read .. however, this gets mapped to 0 in sock_read and the call returns
0.

I would like to if there is anyway I can detect when memcpy_iovec is
called that it is coming as a consequence of my system call so that I can
process the data in a different manner ? I don't want to change the
prototype of all the function in between as that would be extremely messy.

Thanks in Advance,
Koushik.

***********************************************************************
 Koushik Chakraborty
 Senior Undergraduate,
 Dept. of Computer Science and Engineering.
 Indian Institute of Technology,Kanpur
 India.
 ------------------------------------------------------------------
 Contact Address :- E-mail :

  Room no. A111, Hall - 1 kchak@iitk.ac.in.
  IIT Kanpur, kchak@mailcity.com
  Pin 208016.
  India.

***********************************************************************

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Mon Jan 31 2000 - 21:00:23 EST