Multithreading in C in Different CPU core

# define _GNU_SOURCE
# include <stdio.h>
# include <math.h>
# include <stdlib.h>
# include <pthread.h>
# include <stdlib.h>

pthread_mutex_t mux = PTHREAD_MUTEX_INITIALIZER;


struct p2p{
int st;
int en;
};

void *primeChk(void* val);

int main()
{
  pthread_t thread1,thread2,thread3,thread4;
  struct p2p valu1,valu2,valu3,valu4;
  int j,ret1,ret2,ret3,ret4;
  cpu_set_t cpuset;

// pthread_setaffinity_np(thread, sizeof(cpu_set_t), &cpuset);


  valu1.st = 1;
  valu1.en = 5000;
  valu2.st = 5001;
  valu2.en = 10000;
  valu3.st = 10001;
  valu3.en = 15000;
  valu4.st = 15001;
  valu4.en = 20000;

   // initialization
   CPU_ZERO(&cpuset);


   CPU_SET(0,&cpuset);
   pthread_setaffinity_np(thread1, sizeof(cpu_set_t), &cpuset);
   ret1 = pthread_create(&thread1,NULL,&primeChk,(void*)&valu1);
   //CPU_ZERO(&cpuset); 

   CPU_SET(1,&cpuset);
   pthread_setaffinity_np(thread2, sizeof(cpu_set_t), &cpuset);
   ret2 = pthread_create(&thread2,NULL,&primeChk,(void*)&valu2);
  // CPU_ZERO(&cpuset);
/*      
    CPU_SET(2,&cpuset);
    pthread_setaffinity_np(thread3, sizeof(cpu_set_t), &cpuset);
    ret3 = pthread_create(&thread3,NULL,&primeChk,(void*)&valu3);
   
   CPU_SET(3,&cpuset);
   pthread_setaffinity_np(thread4, sizeof(cpu_set_t), &cpuset);
   ret4 = pthread_create(&thread4,NULL,&primeChk,(void*)&valu4);
  */

  pthread_join(thread1,NULL);
  pthread_join(thread2,NULL);
 // pthread_join(thread3,NULL);
 // pthread_join(thread4,NULL);

  return 0;
}


void *primeChk(void *val)
{
  struct p2p *valu = (struct p2p *)val;
  int str,end,i,k,j,l,m;

 // pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);
  str = valu->st;
  end = valu->en;
  if(str == 1)
  printf("%d",++str);

  pthread_mutex_lock(&mux);
  for(i=str;i<=end;i++)
  {
     k = sqrt(i);l = 0;
     for(j=2;j<=k+1;j++)
     if(i % j == 0)
     {
        l = 1;break;
     }
     if(l == 0)printf(" %d",i);
  }
  pthread_mutex_unlock(&mux);

  //pthread_getaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);
 // printf("\nSet returned by pthread_getaffinity_np() contained:\n");
 // for (j = 0; j < CPU_SETSIZE; j++)
   //    if (CPU_ISSET(j, &cpuset))
    //   printf("    CPU %d\n", j);


}

UDP server client in c

Server

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>

int main()
{
        int sock;
        int addr_len, bytes_read;
        char recv_data[1024],send_data[1024];
        struct sockaddr_in server_addr , client_addr;


        if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
            perror("Socket");
            exit(1);
        }

        server_addr.sin_family = AF_INET;
        server_addr.sin_port = htons(5000);
        server_addr.sin_addr.s_addr = INADDR_ANY;
        bzero(&(server_addr.sin_zero),8);


        if (bind(sock,(struct sockaddr *)&server_addr,
            sizeof(struct sockaddr)) == -1)
        {
            perror("Bind");
            exit(1);
        }

        addr_len = sizeof(struct sockaddr);

        printf("\nUDPServer Waiting for client on port 5000");
        fflush(stdout);

        int count = 0,i;
        char a[20][10],d[20][10];
        strcpy(a[0],"A");
        strcpy(a[1],"B");
        strcpy(a[2],"C");
        strcpy(a[3],"D");
        strcpy(d[0],"123");
        strcpy(d[1],"124");
        strcpy(d[2],"100");
        strcpy(d[3],"99");

        while (1)
        {

          bytes_read = recvfrom(sock,recv_data,1024,0,
                            (struct sockaddr *)&client_addr, &addr_len);


          recv_data[bytes_read] = '\0';

          printf("\n(%s , %d) said : ",inet_ntoa(client_addr.sin_addr),
                                       ntohs(client_addr.sin_port));
          printf("%s", recv_data);
          printf("SEND : ");
         // gets(send_data);

             int p = 0;
                 for(i=0;i<4;i++)
                 {
                        if(strcmp(recv_data,d[i]) == 0)
                        {
                             strcpy(send_data,a[i]);p=1;
                        }
                 }
                 if(p == 0)
                 strcpy(send_data,"No one on that role.");

          sendto(sock,send_data,strlen(send_data),0,(struct sockaddr *)&client_addr,sizeof(struct sockaddr));

          fflush(stdout);

        }
        return 0;
}
CLIENT
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>

int main()
{
int sock,bytes_recv,sin_size;
struct sockaddr_in server_addr;
struct hostent *host;
char send_data[1024],recv_data[1024];

host= (struct hostent *) gethostbyname((char *)"127.0.0.1");


if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
{
perror("socket");
exit(1);
}

server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(5000);
server_addr.sin_addr = *((struct in_addr *)host->h_addr);
bzero(&(server_addr.sin_zero),8);
sin_size = sizeof(struct sockaddr);

   while (1)
   {

    printf("Type Something (q or Q to quit):");
    gets(send_data);

    if ((strcmp(send_data , "q") == 0) || strcmp(send_data , "Q") == 0)
       break;

    else
       sendto(sock, send_data, strlen(send_data), 0,
              (struct sockaddr *)&server_addr, sizeof(struct sockaddr));

         bytes_recv = recvfrom(sock,recv_data,1024,0,(struct sockaddr *)&server_addr,&sin_size);
          recv_data[bytes_recv]= '\0';
     printf("Received :%s\n",recv_data);
   }

}


TCP server client in C

Client Code
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>


int main()

{

        int sock, bytes_recieved;
        char send_data[1024],recv_data[1024];
        struct hostent *host;
        struct sockaddr_in server_addr;

        host = gethostbyname("127.0.0.1");

        sock = socket(AF_INET, SOCK_STREAM,0);

        server_addr.sin_family = AF_INET;
        server_addr.sin_port = htons(5000);
        server_addr.sin_addr = *((struct in_addr *)host->h_addr);
        bzero(&(server_addr.sin_zero),8);

        connect(sock, (struct sockaddr *)&server_addr,sizeof(struct sockaddr));

        while(1)
        {

          bytes_recieved=recv(sock,recv_data,1024,0);
          recv_data[bytes_recieved] = '\0';

           printf("\nRecieved data = %s " , recv_data);
           printf("\nSend Data :");

           gets(send_data);

           send(sock,send_data,strlen(send_data), 0);

        }
return 0;
} 
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>


int main()
{
        int sock, connected, bytes_recieved , true = 1;
        char send_data [1024] , recv_data[1024];

        struct sockaddr_in server_addr,client_addr;
        int sin_size;

        sock = socket(AF_INET, SOCK_STREAM, 0);
       // setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,&true,sizeof(int));

        server_addr.sin_family = AF_INET;
        server_addr.sin_port = htons(5000);
        server_addr.sin_addr.s_addr = INADDR_ANY;
        bzero(&(server_addr.sin_zero),8);
        printf("%d\n",sock);
        bind(sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr));

        listen(sock, 5);
        printf("\nTCPServer Waiting for client on port 5000");
        fflush(stdout);
        int count = 0,i;
        char a[20][10],d[20][10];
        strcpy(a[0],"A");
        strcpy(a[1],"B");
        strcpy(a[2],"C");
        strcpy(a[3],"D");
        strcpy(d[0],"123");
        strcpy(d[1],"124");
        strcpy(d[2],"100");
        strcpy(d[3],"99");

        while(1)
        {

            sin_size = sizeof(struct sockaddr_in);

            connected = accept(sock, (struct sockaddr *)&client_addr,&sin_size);

            printf("\n I got a connection from (%s , %d)",
                   inet_ntoa(client_addr.sin_addr),ntohs(client_addr.sin_port));

            while (1)
            {
                ++count;
                 printf("\n SEND : ");
                 //gets(send_data);

                 if(count == 1)
                 strcpy(send_data,"Welcome to TCPServer");
                 send(connected, send_data,strlen(send_data), 0);

                 bytes_recieved = recv(connected,recv_data,1024,0);

                 recv_data[bytes_recieved] = '\0';

                 printf("\n RECIEVED DATA = %s " , recv_data);
                 int p = 0;
                 for(i=0;i<4;i++)
                 {
                        if(strcmp(recv_data,d[i]) == 0)
                        {
                             strcpy(send_data,a[i]);p=1;
                        }
                 }
                 if(p == 0)
                 strcpy(send_data,"No one on that role.");
                 fflush(stdout);
            }
        }

      close(sock);
      return 0;
}