Hello I need to submit this exercise until the end of the day of the $18$th of may.

I have to write a code using Language C $($Fedora$,$ Linux$).$ If requested I insert also my student number: $1230065.$

I also insert this code sent by the professor to check if the code works correctly:

#$!/$bin$/$bash

if $[[$ $# $-$eq $0]]$ ; then

echo 'Utiliza$$o:$\text{'}$ $$0\text{'}$n$$mero$\_$de$\_$estudante'

exit $0$

fi

CFILES$=$$$($echo $-$e $"$ex$2\_$clt$.$c

ex$2\_$srv$.$c

ex$3\_$clt$.$c

ex$3\_$srv$.$c

ex$4\_$clt$.$c

ex$4\_$srv$.$c

ex$5\_$clt$.$c

ex$5\_$srv$.$c

ex$8$a$.$c

ex$8$b$.$c$")$

OIFS$="$$IFS"

IFS$=$$$\text{'}$

$\text{'}$

for file in $CFILES

do

ls $$\{$file$\}$ &$>/$dev$/$null $||$ echo Ficheiro $\backslash "$$file$\backslash "$ n$$o encontrado.

execfile$=$$$\{$file$\%.$c$\}$

ls $$\{$execfile$\}$ &$>/$dev$/$null && $($ grep $"$$$1"$ $$\{$execfile$\}$ &$>/$dev$/$null $||$ echo Verifique se faz a impress$$o solicitada em $\backslash "$$$\{$file$\}\backslash ")||$ echo Ficheiro $\backslash "$$execfile$\backslash "$ n$$o encontrado.

done

IFS$="$$OIF"

Here it is the exercise:

Exercise $8$

a$)$ Implement a program that is able to receive text messages through UDP $3000$ port and print

them, as well as the sender$\text{'}$s IP address and port number, on the screen.

b$)$ Implement a program that allows sending messages to the program described in point $1$

until it is finished with the combination ctrl$+$c$.$

c$)$ Check that the initial program can receive sequences of messages from different clients

without resorting to any type of multi$-$tasking mechanism $($creation of new processes or

threads$).$

d$)$ The maximum size of IPv$4$ packets is $65536$ bytes. However, in general, the connection

layer $($e$.$g$.,$ the ethernet network$)$ does not allow sending packets of this length. The IPv$4$

protocol supports a fragmentation mechanism in order to overcome this limitation$.$

However, this mechanism has some disadvantages so$,$ in Linux, it is disabled by default for

UDP. Check, by trial and error $($it can also be based on the information provided by the

ifconfig command$),$ the maximum size that messages can have to be sent successfully.