socket interface in Unix/Linux

niranjan.patil007 · 11-07-2009, 12:42 PM

I am doing a program using sockets under Unix./Linux in user space.
I include file sys/socket.h

Also i have seen socket implementation in Linux Kernel Source tree under net/sock.h

My question is :- Does sys/scocket.h makes use of net/sock.h as a kernel level implementation, by this way does it act as a posix interface between user programm and actual kernel level implementation of scockets?

Thanks
Niranjan

paulsm4 · 11-07-2009, 03:10 PM

No.

For all intents and purposes, this *is* the interface:
http://beej.us/guide/bgnet/output/ht...l#simpleclient

Code:

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>

#include <arpa/inet.h>

This does NOT (repeat - does NOT) translate directly to the underlying kernel implementation. In practice, there are great similarities, and relatively little overhead. But from your perspective (the perspective of the application programming, running in user space), the socket library and the underlying implementation are COMPLETELY SEPARATE AND INDEPENDENT.

Make sense?

'Hope that helps .. PSM