tcp_client.c

#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>
#include <arpa/inet.h>

int main(int argc, char *argv[]){

    int sfd =0, n=0, b;
    char rbuff[1024];
    char sendbuffer[100000];

    struct sockaddr_in serv_addr;

    memset(rbuff, '0', sizeof(rbuff));
    sfd = socket(AF_INET, SOCK_STREAM, 0);

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_port = htons(5000);
    serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");

    b=connect(sfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
    if (b==-1) {
        perror("Connect");
        return 1;
    }

    FILE *fp = fopen("100MB.img", "rb");
    if(fp == NULL){
        perror("File");
        return 2;
    }

    while( (b = fread(sendbuffer, 1, sizeof(sendbuffer), fp))>0 ){
        send(sfd, sendbuffer, b, 0);
    }

    fclose(fp);
    return 0;

}

tcp_server.c

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

int main(int argc, char *argv[]){

    int fd =0, confd = 0,b,tot;
    struct sockaddr_in serv_addr;

    char buff[100001];
    int num;

    fd = socket(AF_INET, SOCK_STREAM, 0);
    printf("Socket created\n");

    memset(&serv_addr, '0', sizeof(serv_addr));
    memset(buff, '0', sizeof(buff));

    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(5000);

    bind(fd, (struct sockaddr*)&serv_addr, sizeof(serv_addr));
    listen(fd, 10);

    while(1){
        confd = accept(fd, (struct sockaddr*)NULL, NULL);
        if (confd==-1) {
            perror("Accept");
            continue;
        }
        FILE* fp = fopen( "a.jpg", "wb");
        tot=0;
        if(fp != NULL){
            while( (b = recv(confd, buff, 100000,0))> 0 ) {
                tot+=b;
                fwrite(buff, 1, b, fp);
            }

            printf("Received byte: %d\n",tot);
            if (b<0)
               perror("Receiving");

            fclose(fp);
        } else {
            perror("File");
        }
        close(confd);
    }

    return 0;
}

unix and IP socket server-client

## TCP server/client
server writes the file(tcp_server.c) / client reads and sends the file to server(tcp_client.c)

## UNIX server/client
server reads and sends teh file over the network(unix_server.c) / client writes the file server(unix_client.c)

unix_client.c

       #include <errno.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <string.h>
       #include <sys/socket.h>
       #include <sys/un.h>
       #include <unistd.h>
       #include "connection.h"
#include <errno.h>
#include <sys/types.h>

       int
       main(int argc, char *argv[])
       {
           struct sockaddr_un addr;
           int i;
           int ret;
           int data_socket;
           char buffer[BUFFER_SIZE];

           /* Create local socket. */

           data_socket = socket(AF_UNIX, SOCK_SEQPACKET, 0);
           if (data_socket == -1) {
               perror("socket");
               exit(EXIT_FAILURE);
           }

           /*
            * For portability clear the whole structure, since some
            * implementations have additional (nonstandard) fields in
            * the structure.
            */

           memset(&addr, 0, sizeof(struct sockaddr_un));

           /* Connect socket to socket address */

           addr.sun_family = AF_UNIX;
           strncpy(addr.sun_path, SOCKET_NAME, sizeof(addr.sun_path) - 1);

           ret = connect (data_socket, (const struct sockaddr *) &addr,
                          sizeof(struct sockaddr_un));
           if (ret == -1) {
               fprintf(stderr, "The server is down.\n");
               exit(EXIT_FAILURE);
           }

           /* Send arguments. */

      strcpy (buffer, "END");
           ret = write(data_socket, buffer, strlen(buffer) + 1);
           if (ret == -1) {
               perror("write");
               exit(EXIT_FAILURE);
           }

           /* Receive result. */
	   int b;
	   int tot=0;
	FILE* fp = fopen( "a.jpg", "wb");
                 while( (b = recv(data_socket, buffer, 100000,0))> 0 ) {
                tot+=b;
                fwrite(buffer, 1, b, fp);
            }
 	printf("%d", tot);

           /* Ensure buffer is 0-terminated. */

           buffer[BUFFER_SIZE - 1] = 0;

           printf("Result = %s\n", buffer);

           /* Close socket. */

           close(data_socket);

           exit(EXIT_SUCCESS);
       }

unix_server.c

       /*
        * File server.c
        */

       #include <stdio.h>
       #include <stdlib.h>
       #include <string.h>
       #include <sys/socket.h>
       #include <sys/un.h>
       #include <unistd.h>
       #include "connection.h"
#include <sys/types.h>
#include <errno.h>

       int
       main(int argc, char *argv[])
       {
           struct sockaddr_un name;
           int down_flag = 0;
           int ret;
           int connection_socket;
           int data_socket;
           int result;
           char buffer[BUFFER_SIZE];

           /*
            * In case the program exited inadvertently on the last run,
            * remove the socket.
            */

           unlink(SOCKET_NAME);

           /* Create local socket. */

           connection_socket = socket(AF_UNIX, SOCK_SEQPACKET, 0);
           if (connection_socket == -1) {
               perror("socket");
               exit(EXIT_FAILURE);
           }

           /*
            * For portability clear the whole structure, since some
            * implementations have additional (nonstandard) fields in
            * the structure.
            */

           memset(&name, 0, sizeof(struct sockaddr_un));

           /* Bind socket to socket name. */

           name.sun_family = AF_UNIX;
           strncpy(name.sun_path, SOCKET_NAME, sizeof(name.sun_path) - 1);
       ret = bind(connection_socket, (const struct sockaddr *) &name,
                      sizeof(struct sockaddr_un));
           if (ret == -1) {
               perror("bind");
               exit(EXIT_FAILURE);
           }

           /*
            * Prepare for accepting connections. The backlog size is set
            * to 20. So while one request is being processed other requests
            * can be waiting.
            */

           ret = listen(connection_socket, 20);
           if (ret == -1) {
               perror("listen");
               exit(EXIT_FAILURE);
           }

           /* This is the main loop for handling connections. */


               /* Wait for incoming connection. */

               data_socket = accept(connection_socket, NULL, NULL);
               if (data_socket == -1) {
                   perror("accept");
                   exit(EXIT_FAILURE);
               }

               result = 0;

                   /* Wait for next data packet. */

                   ret = read(data_socket, buffer, BUFFER_SIZE);
                   if (ret == -1) {
                       perror("read");
                       exit(EXIT_FAILURE);
                   
		   }
		   int b;
		   FILE *fp = fopen("1GB.img", "rb");

		       while( (b = fread(buffer, 1, sizeof(buffer), fp))>0 ){
        send(data_socket, buffer, b, 0);
    }


                   /* Ensure buffer is 0-terminated. */

                   buffer[BUFFER_SIZE - 1] = 0;
 /* Handle commands. */


               /* Send result. */


               /* Close socket. */

               close(data_socket);



           close(connection_socket);

           /* Unlink the socket. */

           unlink(SOCKET_NAME);

           exit(EXIT_SUCCESS);
       }