When I Am Receiving A File From Android, I Am Having Data Loss At The Last Of The File.

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C

TCP/IP

sockets

I am new to C programming and working on tcp/ip protocol. When we try to communicate from android to C by sending a text file, i am able to receive the text file in partial not the complete file. There is a mismatch in bytes with the source file and the received file.How to eradicate this.

[edit]
// I have given the code for further reference

#include<stdio.h>
#include<unistd.h>
#include<string.h>    
#include<stdlib.h>
#include<sys ioctl.h="">
#include<sys types.h="">
#include<arpa inet.h="">
#include<sys socket.h="">

int a = 1;
char str1[3], str2[] = "ok", str3[] = "no";
char *pBuf;

int receive_text(long long int new_socket)
{
    long int buffersize = 0, recv_size = 0, size = 0, read_size, write_size;
    char verify = '1';
    int errno;
    FILE *text;

    //Find the size of the text
    recv(new_socket, (char *)& size, sizeof(int), 0);
    //Send our verification signal
    send(new_socket, & verify, sizeof(char), 0);
    //Make sure that the size is bigger than 0

    /*if (size <= 0)
    {
    printf("Error has occurred. Size less than or equal to 0 \n");
    return -1;
    }*/

    text = fopen("/home/sosdt009/Desktop/received.txt", "w");
    if (text == NULL)
    {
        puts("Error has occurred. Text file could not be opened \n");
        return -1;
    }

    //Loop while we have not received the entire file yet
    while (recv_size < size)
    {
        ioctl(new_socket, FIONREAD, & buffersize);
        //We check to see if there is data to be read from the socket 
        if (buffersize > 0)
        {
            pBuf = malloc(buffersize);
            if (!pBuf)
            {
                fprintf(stderr, "Memory Error. Cannot allocate!\n");
                exit(-1);
            }
            read_size = recv(new_socket, pBuf, buffersize, 0);
            if (read_size  < 0)
            {
                printf("%s", strerror(errno));
            }

            //Write the currently read data into our text file
            write_size = fwrite(pBuf, 1, buffersize, text);
            free(pBuf);
            //Increment the total number of bytes read
            recv_size += write_size;
        }
    }

    fclose(text);
    //printf("text successfully Received! \n");
    return 1;
}

int main(int argc, char *argv[])
{
    int socket_desc, new_socket, c, read_size, buffer = 0;
    struct sockaddr_in server, client;
    char *readin;

    //Create socket
    socket_desc = socket(AF_INET, SOCK_STREAM, 0);
    if (socket_desc == -1)
    {
        printf("Could not create socket:");
    }

    //Prepare the sockaddr_in structure
    server.sin_family = AF_INET;
    server.sin_addr.s_addr = INADDR_ANY;
    server.sin_port = htons(6777);

    //Bind
    if (bind(socket_desc, (struct sockaddr *)& server, sizeof(server)) < 0)
    {
        puts("bind failed");
        return 1;
    }
    puts("Bind completed");
    //Listen
    listen(socket_desc, 3);

    //Accept and incoming connection
    puts("Waiting for incoming connections...");
    c = sizeof(struct sockaddr_in);
    if ((new_socket = accept(socket_desc, (struct sockaddr *)& client, (socklen_t *)& c)))
    {
        puts("Connection accepted");
    }
    fflush(stdout);
    close(socket_desc);
    if (new_socket< 0)
    {
        perror("Accept Failed");
        return 1;
    }
    while (1)
    {
        receive_text(new_socket);
    }
    close(socket_desc);
    return 0;
}

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