53 lines
2.2 KiB
Plaintext
53 lines
2.2 KiB
Plaintext
|
|
CHARGEN
|
|
|
|
This file implements a nice example of handling multiple tcp sockets in a
|
|
server environment. Just call chargen_init() from your application after
|
|
you have initialized lwip and added your network interfaces. Change the
|
|
MAX_SERV option to increase or decrease the number of sessions supported.
|
|
|
|
chargen will jam as much data as possible into the output socket, so it
|
|
will take up a lot of CPU time. Therefore it will be a good idea to run it
|
|
as the lowest possible priority (just ahead of any idle task).
|
|
|
|
This is also a good example of how to support multiple sessions in an
|
|
embedded system where you might not have fork(). The multiple sessions are
|
|
all handled by the same thread and select() is used for demultiplexing.
|
|
|
|
No makefile is provided, just add chargen to the makefile for your
|
|
application. It is OS and HW independent.
|
|
|
|
Once the chargen server is running in your application, go to another system
|
|
and open a telnet session to your lwip platform at port 19. You should see an
|
|
ASCII pattern start to stream on you screen.
|
|
|
|
As an example, lets say that your system running lwip is at IP address
|
|
192.168.10.244 and you have a linux system connected to it at IP address
|
|
192.168.10.59. Issue the following command at a terminal prompt on the linux system:
|
|
|
|
telnet 192.168.10.244 19
|
|
|
|
You will see a pattern similar to the following on streaming by on your
|
|
screen:
|
|
|
|
ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{
|
|
BCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|
|
|
CDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}
|
|
DEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
|
|
EFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!
|
|
FGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"
|
|
GHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#
|
|
HIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$
|
|
IJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%
|
|
JKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%&
|
|
KLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%&'
|
|
LMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%&'(
|
|
|
|
It even works from windows: At a dos prompt you can also issue the same
|
|
telnet command and you will get a similar (but much slower, at least on W98)
|
|
data stream.
|
|
|
|
David Haas
|
|
|
|
|