#include <stdio.h>  /* printf */
#include <sys/socket.h>  /* socket, bind, listen */
#include <arpa/inet.h>  /* htonl */
#include <string.h>   /* strcpy */
#include <pthread.h>

pthread_mutex_t mutex=PTHREAD_MUTEX_INITIALIZER;
char line[256]="";

void * udpMonitorServer( void * p_port) {
    int port = *((int *)p_port);
    int udpSocket, rc, len;
    struct sockaddr_in name, from;
    char buf[10];

    udpSocket = socket(AF_INET, SOCK_DGRAM, 0);
    name.sin_family = AF_INET;
    name.sin_port = htons(port);
    name.sin_addr.s_addr = htonl(INADDR_ANY);
    len = sizeof(struct sockaddr_in);
    if( bind(udpSocket, (struct sockaddr *) &name, len))
        printf("bind error");
    len = sizeof(from);
    for(;;){
        printf("\n... UDP server is waiting...\n");
        if ((rc=recvfrom(udpSocket, buf, sizeof(buf), 0, (struct sockaddr *)&from, &len)) < 0)
            perror("receiving datagram  message");
        if ((rc > 0) && (buf[0]=='n') ){
            pthread_mutex_lock(&mutex);
            if (sendto(udpSocket, line, strlen(line), 0,(struct sockaddr *) &from, sizeof(from)) <0 )
                perror("sending line");
            pthread_mutex_unlock(&mutex);
        }
   }    
}

#include <pthread.h>
#include <unistd.h>   /* read,  close */
#include <stdlib.h>  /* exit */

int main(int argc, char *argv[])  {
    int port = atoi(argv[1]);
    pthread_t tid;
    int welcomeSocket, generatorSocket, len;
    struct sockaddr_in name;
    int n;
    char buff[buffSize];

    pthread_create(&tid, NULL, udpMonitorServer, &port);  

    welcomeSocket = socket(AF_INET, SOCK_STREAM, 0);
    name.sin_family = AF_INET;
    name.sin_port = htons(port);
    name.sin_addr.s_addr = htonl(INADDR_ANY);
    len = sizeof(struct sockaddr_in);
    if( bind(welcomeSocket, (struct sockaddr *) &name, len))
        printf("bind error");
    listen(welcomeSocket, 5);
    printf("\n... TCP server is waiting...\n");
    generatorSocket = accept(welcomeSocket, (struct sockaddr *) &name, &len);
    do {
        n = read(generatorSocket, buff, sizeof(buff));
        if (n > 0) {
            buff[n]='\0';
            printf("\n... TCP server received:%s\n", buff);
            pthread_mutex_lock(&mutex);
            strcpy(line, buff);
            pthread_mutex_unlock(&mutex);
        }
    } while ( n > 0);
    close(generatorSocket);
    close(welcomeSocket);
    exit(0);
}