C Language Programming example of socket communication program based on TCP and UDP protocol _c language

TCP multithreaded Server and client program
Server program:

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <arpa/inet.h> #include < sys/types.h> #include <sys/socket.h> #include <unistd.h> #define PORT 8082 #define BufSize Char Buf[buf

SIZE+1];
    void* Fun (void* x) {//printf ("enter thread!\r\n");
  int new_fd=* ((int*) x); while (1) {int z=read (new_fd,buf,bufsize);//step 6th reads socket if (z==0) {printf ("Client close!");
  break;};
  Buf[z]= ' ";
printf ("%s\r\n", buf);//print};
int newfd[512];
int inewfd=0;
  int main () {//step 1th creates socket int sockfd=socket (af_inet,sock_stream,0);
  The 2nd step is to set the address structure body struct sockaddr_in svraddr;
  svraddr.sin_family=af_inet;//uses Internet Protocol svraddr.sin_port=htons (port);
  Inet_aton ("0.0.0.0", &svraddr.sin_addr);
    Step 3rd Binding int Ret=bind (SOCKFD, (struct sockaddr*) &svraddr,sizeof (SVRADDR));
  if (ret<0) {printf ("error bind!\r\n"); exit (-1);};
  4th Step Monitoring Listen (sockfd,128); while (1) {newfd[inewfd++]=accept (Sockfd,null,nulL);
    The 5th step receives pthread_t Ntid; 
  Pthread_create (&ntid,null,fun, (void*) & (Newfd[inewfd-1));

 }
}

Attention:

GCC Server.c-o server-lpthread

Client program CLI.C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h >
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#define PORT 8082
#define BufSize
Char buf[bufsize+1];
int main ()
{
  //step 1th creates an individual socket
  int sockfd=socket (af_inet,sock_stream,0);
  The 2nd step is to set up the addr structure body
  struct sockaddr_in svraddr;
  svraddr.sin_family=af_inet;//uses Internet Protocol
  svraddr.sin_port=htons (port);
  Inet_aton ("127.0.0.1", &svraddr.sin_addr);
  The 3rd step connects server Connect
  (SOCKFD, (struct sockaddr*) &svraddr,sizeof (svraddr));
  while (1)
  {
  scanf ("%s", buf);
  Write (Sockfd,buf,strlen (BUF)); Step 4th writes the string to a socket
  }
}

server programs and client programs for UDP

Server program:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h >
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#define PORT 8082
#define BufSize
Char buf[bufsize+1];
int main ()
{
  //step 1th creates socket
  int sockfd=socket (af_inet,sock_dgram,0);
  The 2nd step is to set the address structure body
  struct sockaddr_in svraddr;
  svraddr.sin_family=af_inet;//uses Internet Protocol
  svraddr.sin_port=htons (port);
  Inet_aton ("0.0.0.0", &svraddr.sin_addr);
  Step 3rd binding
  int Ret=bind (SOCKFD, (struct sockaddr*) &svraddr,sizeof (svraddr));
  if (ret<0) {printf ("Cannot bind!\r\n"); exit ( -1);};
  while (1)
  {
        struct sockaddr_in cli;
        int len=sizeof (CLI);
    int Z=recvfrom (sockfd,buf,bufsize,0, (struct sockaddr*) &cli,&len);//6th step read socket  
    buf[z]= ' "";
    printf ("%s\r\n", buf);//Print
  }

}

Client program CLI.C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h >
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#define PORT 8082
#define BufSize
Char buf[bufsize+1];
int main ()
{
  //step 1th creates an individual socket
  int sockfd=socket (af_inet,sock_dgram,0);
  The 2nd step is to set up the addr structure body
  struct sockaddr_in svraddr;
  svraddr.sin_family=af_inet;//uses Internet Protocol
  svraddr.sin_port=htons (port);
  Inet_aton ("127.0.0.1", &svraddr.sin_addr);
  The 3rd step connects
  the server//connect (SOCKFD, (struct sockaddr*) &svraddr,sizeof (svraddr));
  while (1)
  {
  scanf ("%s", buf);
  SendTo (Sockfd,buf,strlen (BUF), 0, (struct sockaddr*) &svraddr,sizeof (SVRADDR)); Step 4th writes the string to a socket
  }
}