Concept Of Lan Chat

[shakti5385]

Hi all :wave:
Another concept coming in my mind my project running at the task bar and I am showing it at startup using some code…..
When we click on mouse at the start up the pop up (msn type) form appear…
And when pc start pc name saved in the database
A combo is appearing showing all pc names that are presently login….
Database is at server….
What I want that I select a pc name from the combo…..
And type a message then the message goes to another pc….

Or directly I want to say have u any concepts of LAN chat….? :confused:
How To Start

Thanks

[Al42]

Netsend?

[shakti5385]

Netsend?
what...

[Al42]

And type a message then the message goes to another pc….You described the program named Netsend.

[shakti5385]

You described the program named Netsend.
so what happen?

[Al42]

I was just saying that what you want to write was written decades ago. If you search for Netsend source you'll probably find hundreds of hits.

[shakti5385]

If U R Able To Send Me The Link Then It Is Very Best Idea ;)

[Al42]

http://www.ostrosoft.com/vb/projects/net_send/index.asp

There are a lot of others at http://www.google.com/search?q=netsend%2Bsource&start=0&ie=utf-8&oe=utf-8&client=firefox-a&rls=org.mozilla:en-US:official, but that one is in VB.

[rory]

if it uses the Messenger Service,
Messenger Service is disabled in XP SP2 by default as is a security risk ..

[shakti5385]

i am checking

[shakti5385]

http://www.ostrosoft.com/vb/projects/net_send/index.asp
this very help full.... again i am testing..........
please some wait...
thanks

[dilettante]

While there is a known buffer overrun vulnerability in the Windows Messenger Service in NT operating systems (NT 4.0, 2000, XP, 2003) there is a patch for it too. Microsoft Security Bulletin MS03-043 (http://www.microsoft.com/technet/security/bulletin/ms03-043.mspx).

These are just an inevitability when you use software written in unsafe languages like C. The only cure is lots of eyeballs going over the code for bugs like this, one answer perhaps being to use OpenBSD where the code is heavily scrutinized.

All that said, there is nothing inherently unsafe in the communications infrastructure used by NET SEND and the Messenger Service (or WinPopup on Win9x systems). Windows Networking Mailslots are a really nice little UDP-like communication technology.


As long as you have NetBIOS connectivity between systems and they are in the same Workgroup or Domain Mailslots work nicely for LAN messaging. One advantage is that you don't need to tie up a TCP port number, the traffic is multiplexed over the channels used for File and Print Sharing services. Another is that Mailslots programs work transparently over TCP/IP, IPX, or even NetBEUI. Yet another is the vast namespace available with Mailslots, unlike the 64K of port numbers used for TCP/IP.

Mailslots also present some small obstacles. Nothing is perfect.

One thing is that only one instance of a given Mailslot can exist on a machine - but that's a lot like saying only one program can Bind to a given TCP or UDP port. Another is that in when machines allow NetBIOS over multiple protocols (TCP/IP and IPX for example) a message sent to a Mailslot will get there once for each protocol in use. The datagram limit is also 424 bytes for Mailslot broadcasts.

The big thing is that there isn't any standard ActiveX component for doing Mailslots. Instead you have to code to the API. See About Mailslots (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/ipc/base/about_mailslots.asp?frame=true) for details.

[rory]

http://www.grc.com/stm/shootthemessenger.htm

[k1ll3rdr4g0n]

I'm sorry, but I can barley understand what you are trying to do...

But my best bet would to send a message to the broadcast address on your network asking who is out there, and the client program (that you write) would respond "I'm here!" (ok not exactly that...maybe a certain byte if the user is at the computer, 0x01, logged out, 0x02...ect).
And creating it from there is a basic relay server, (unless you want usernames/passwords, even then it wouldn't be that hard).

[shakti5385]

i am cecking wait ...