giuliomoro@28: /* UDP client in the internet domain */
giuliomoro@28: #include <sys/types.h>
giuliomoro@28: #include <sys/socket.h>
giuliomoro@28: #include <netinet/in.h>
giuliomoro@28: #include <arpa/inet.h>
giuliomoro@28: #include <netdb.h>
giuliomoro@28: #include <stdio.h>
giuliomoro@28: #include <stdlib.h>
giuliomoro@28: #include <unistd.h>
giuliomoro@28: #include <string.h>
giuliomoro@28: 
giuliomoro@28: void error(const char *);
giuliomoro@28: int main(int argc, char *argv[])
giuliomoro@28: {
giuliomoro@28:    int sock, n;
giuliomoro@28:    unsigned int length;
giuliomoro@28:    struct sockaddr_in server, from;
giuliomoro@28:    struct hostent *hp;
giuliomoro@28:    char buffer[256];
giuliomoro@28:    
giuliomoro@28:    if (argc != 3) { printf("Usage: server port\n");
giuliomoro@28:                     exit(1);
giuliomoro@28:    }
giuliomoro@28: 
giuliomoro@28:    server.sin_family = AF_INET;
giuliomoro@28:    hp = gethostbyname(argv[1]);
giuliomoro@28:    if (hp==0) error("Unknown host");
giuliomoro@28: 
giuliomoro@28:    bcopy((char *)hp->h_addr, 
giuliomoro@28:         (char *)&server.sin_addr,
giuliomoro@28:          hp->h_length);
giuliomoro@28:    server.sin_port = htons(atoi(argv[2]));
giuliomoro@28:    length=sizeof(struct sockaddr_in);
giuliomoro@28:    while (1){
giuliomoro@28:      sock= socket(AF_INET, SOCK_DGRAM, 0);
giuliomoro@28:      if (sock < 0) error("socket");
giuliomoro@28:      bzero(buffer,256);
giuliomoro@28: //     printf("Please enter the message: ");
giuliomoro@28: //     fgets(buffer,255,stdin);
giuliomoro@28:      double freq=50;
giuliomoro@28:      while(1){
giuliomoro@28:        freq*=1.001;
giuliomoro@28:        if(freq>20000) freq=50;
giuliomoro@28:        sprintf(buffer,"%.4f;",freq);
giuliomoro@28:        n=sendto(sock,buffer,
giuliomoro@28:             strlen(buffer),0,(const struct sockaddr *)&server,length);
giuliomoro@28:        if (n < 0) error("Sendto");
giuliomoro@28:        usleep(1000);
giuliomoro@28:      }
giuliomoro@28:    }
giuliomoro@28:    close(sock);
giuliomoro@28:    return 0;
giuliomoro@28: }
giuliomoro@28: 
giuliomoro@28: void error(const char *msg)
giuliomoro@28: {
giuliomoro@28:     perror(msg);
giuliomoro@28:     exit(0);
giuliomoro@28: }