#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
void main(void)
{
struct sockaddr_in me, client;
int sock=socket(AF_INET,SOCK_DGRAM,0);
int adl=sizeof(me);
char linha[81], *aux;
bzero((char *)&me,adl);
me.sin_family=AF_INET;
me.sin_addr.s_addr=htonl(INADDR_ANY); /* endereco IP local */
me.sin_port=htons(8450); /* porta local  */
if(-1!=bind(sock,(struct sockaddr *)&me,adl))
do
        {
        recvfrom(sock,linha,81,0,(struct sockaddr *)&client,&adl);
        aux=linha;while(*aux) {*aux=toupper(*aux);aux++;}
        sendto(sock,linha,81,0,(struct sockaddr *)&client,adl);
        }
while(strcmp(linha,"EXIT"));
else puts("Porta ocupada");
close(sock);
}