D. TCP File Transfer Socket Programming in Unix Using C Programming

FILE TRANSFER SERVER USING TCP

/*FILE TRANSFER SERVER USING TCP IN C*/
#include<netinet/in.h> 
#include <sys/types.h> 
#include <sys/socket.h> 
#include<stdio.h> 
#include <arpa/inet.h> 
#include <string.h> 
#include<fcntl.h> 
main() {
   int sd, cd;
   char buf[1000] = "", fname[10];
   struct sockaddr_in ser;
   sd = socket(AF_INET, SOCK_STREAM, 0);
   if (sd < 0)
      printf("SOCKET NOT CREATED\n");
   bzero(&ser, sizeof (struct sockaddr_in));
   ser.sin_family = AF_INET;
   ser.sin_port = htons(1101);
   inet_aton("localhost", &ser.sin_addr);
   int b = bind(sd, (struct sockaddr *) &ser, sizeof (ser));
   printf("BIND VALUE:%d\n", b);
   listen(sd, 5);
   for (;;) {
      cd = accept(sd, NULL, NULL);
      int pid = fork();
      if (pid == 0) {
         printf("accept value %d\n", cd);
         read(cd, buf, 1000);
         int fd = open(buf, O_RDONLY);
         read(fd, buf, 1000);
         write(cd, buf, strlen(buf));
         printf("MESSAGE FROM CLIENT:%s\n", buf);
         close(cd);
      }
   }
   close(sd);
}

FILE TRANSFER CLIENT USING TCP

/*FILE TRANSFER CLIENT USING TCP IN C*/

#include<netinet/in.h> 
#include <sys/types.h> 
#include <sys/socket.h> 
#include<stdio.h> 
#include <arpa/inet.h> 
#include <string.h> 
#include<fcntl.h> 
main() {
   int sd, cd;
   char buf[1000] = "", buf1[1000] = "";
   struct sockaddr_in ser;
   sd = socket(AF_INET, SOCK_STREAM, 0);
   if (sd < 0)
      printf("SOCKET NOT CREATED\n");
   bzero(&ser, sizeof (struct sockaddr_in));
   ser.sin_family = AF_INET;
   ser.sin_port = htons(1101);
   inet_aton("localhost", &ser.sin_addr);
   connect(sd, (struct sockaddr *) &ser, sizeof (ser));
   for (;;) {
      printf("ENTER THE MESSAGE");
      scanf("%s", buf);
      write(sd, buf, strlen(buf));
      read(sd, buf, 1000);
      printf("RECEIVED FROM SERVER%s\n", buf);
   }
   close(sd);
}

Sample Server Output:

cc udp.c - o udp
. / udp
BIND VALUE : 0
accept value 4
MESSAGE FROM CLIENT :
#include<stdio.h> 
main() {
   printf("hello");
}

Sample Client Output:

cc ftclient.c - o ftcli
. / ftcli
ENTER THE MESSAGE
hello.c
RECEIVED FROM SERVER
#include<stdio.h> 
main() {
   printf("hello");
}