UDP source port

[slaskbrev1]

Hi.
Im sending data over a SOCK_DGRAM socket, is it possible to define
what source port my program will use?
I guess one alternative is to craft the UDP header by myself, what
type of socket would I use then? Do I have to craft the IP header
aswell and use SOCK_RAW?

Thanks

[Antoninus Twink]

On 17 Apr 2008 at 9:34, sl********@gmail.com wrote:

Im sending data over a SOCK_DGRAM socket, is it possible to define
what source port my program will use?

Yes - just set the sin_port field of the struct sockaddr *address
argument you give to bind(). (The default value of 0 for sin_port just
means "pick any available port".)

[slaskbrev1]

On 17 Apr, 12:43, Antoninus Twink <[e-mail]:

On 17 Apr 2008 at 9:34, [e-mail] wrote:

Im sending data over a SOCK_DGRAM socket, is it possible to define
what source port my program will use?

Yes - just set the sin_port field of the struct sockaddr *address
argument you give to bind(). (The default value of 0 for sin_port just
means "pick any available port".)

Thanks. It bothers me I didnt figure that out myself. :)

[Keith Thompson]

sl********@gmail.com writes:

Im sending data over a SOCK_DGRAM socket, is it possible to define
what source port my program will use?
I guess one alternative is to craft the UDP header by myself, what
type of socket would I use then? Do I have to craft the IP header
aswell and use SOCK_RAW?

Please ask in a newsgroup that discusses your operating system,
perhaps comp.unix.programmer or one of the Windows groups.

--
Keith Thompson (The_Other_Keith) <ks***@mib.org>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

[ionic]

Call bind() right after socket(), specify your local port and NIC
adapter in sockaddr_in.