I've been using OpenWRT for some time primarly for research in the University. I've also started with some basic network programming (sending UDP packets for instance). But since most of the available tutorials on unix network programming are more related to ethernet programming, I'm not sure if using it for wireless interfaces would be the same. I would like to know if there's any difference between ethernet and wireless raw socket programming.
I would also like to do some raw packets sniffing on a wireless interface "eth1". What structures should I use in order to read the prism headers in monitor mode? I've taken a look here and I can see that it's ok to use these structures:
Has anyone done some wireless network programming/scripting?
I'm running OpenWRT on a WRT54G-TM, Broadcom BCM5352 chip, Linux 2.4.35.4.
I'm working on my homework to write a chatroom program. Different users can be on-line at the same and talk to each other.
I found that each time I invoked the accept function. A new socket was created. I don't how can I receive message from the client who is already on-line and send it to others.... (0 Replies)
I am going to purchase Unix Network Programming by Stevens. The only question I have is which edition to buy. The older (early 90's) edition, or the newer (late 90's) edition. I know conventional thinking would point to the latest ( and greatest?), but I wanted to get some feedback from the forum.... (3 Replies)
Good day everyone,
Please help if you are interested in.
I need to do a chat client-server program.
Does anyone know where I can get references or sample programs?
Thank you very much for your time
Eric (2 Replies)
I want to develop a hybrid IM application which will consist of a chat and an offline messaging (BBS) part.
Server must support
Multiple connection (concurrent)
Arguments should not be hard coded (code will be checked at different machines)
No input at the command line
Must run in the... (3 Replies)
Hi!
I am working on fedora..
trying to execute BSD4.4 client-server program which includes "unp.h" header file...
While executing make command, I got error like,
" expected " , " , " ; ",or ")" in connect_nonb file...ERROR 1 "
I tried to change mode of makefile but I can't get... (4 Replies)
I have written a client-server program which does some data from a file in server to the client. In this I don't want the client to wait indefinitely if server is not running. For this I am using SELECT system call, in this system call we can specify timings as an argument, which tells the client... (2 Replies)
Hi,
I have to start doing network programming in C/Unix but I have windows installed.
Could someone please guide me how to set up the environment best suited for the networking programming?
Regards
Vinayak (1 Reply)
I have started reading the book Unix Network Programming, Volume 1: The Sockets Networking API. I downloaded all the source code and the readme says I must make the files.
zuro@zuro:~/book/unpv12e$ cd lib
zuro@zuro:~/book/unpv12e/lib$ make
gcc -g -O2 -D_REENTRANT -Wall -c -o... (5 Replies)
I have started reading the book Unix Network Programming, Volume 1: The Sockets Networking API. I downloaded all the source code and performed all the steps present in README file.Now when i compile my first program it give the following error.
sainandan@nandan:~/unpv13e/intro$ ./daytimetcpcli... (1 Reply)
Discussion started by: bsainandan
1 Replies
LEARN ABOUT BSD
udp
UDP(4P)UDP(4P)NAME
udp - Internet User Datagram Protocol
SYNOPSIS
#include <sys/socket.h>
#include <netinet/in.h>
s = socket(AF_INET, SOCK_DGRAM, 0);
DESCRIPTION
UDP is a simple, unreliable datagram protocol which is used to support the SOCK_DGRAM abstraction for the Internet protocol family. UDP
sockets are connectionless, and are normally used with the sendto and recvfrom calls, though the connect(2) call may also be used to fix
the destination for future packets (in which case the recv(2) or read(2) and send(2) or write(2) system calls may be used).
UDP address formats are identical to those used by TCP. In particular UDP provides a port identifier in addition to the normal Internet
address format. Note that the UDP port space is separate from the TCP port space (i.e. a UDP port may not be "connected" to a TCP port).
In addition broadcast packets may be sent (assuming the underlying network supports this) by using a reserved "broadcast address"; this
address is network interface dependent.
Options at the IP transport level may be used with UDP; see ip(4P).
DIAGNOSTICS
A socket operation may fail with one of the following errors returned:
[EISCONN] when trying to establish a connection on a socket which already has one, or when trying to send a datagram with the destina-
tion address specified and the socket is already connected;
[ENOTCONN] when trying to send a datagram, but no destination address is specified, and the socket hasn't been connected;
[ENOBUFS] when the system runs out of memory for an internal data structure;
[EADDRINUSE] when an attempt is made to create a socket with a port which has already been allocated;
[EADDRNOTAVAIL]
when an attempt is made to create a socket with a network address for which no network interface exists.
SEE ALSO getsockopt(2), recv(2), send(2), socket(2), intro(4N), inet(4F), ip(4P)4.2 Berkeley Distribution May 16, 1986 UDP(4P)