send() to send data
recv() to receive data

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

#define PORTNUM 1995

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

    int mysocket, consocket, socksize;
    struct sockaddr_in dest;
    struct sockaddr_in serv;
    socksize = sizeof(struct sockaddr_in);
    memset(&dest, 0, sizeof(dest));
    serv.sin_family = AF_INET;
    serv.sin_addr.s_addr = INADDR_ANY;
    serv.sin_port = htons(PORTNUM);
    mysocket = socket(AF_INET, SOCK_STREAM, 0);
    bind(mysocket, (struct sockaddr *)&serv, sizeof(struct sockaddr));
    listen(mysocket, 1);
    int i= 0;

    char buf[50];
    consocket = accept(mysocket, (struct sockaddr *)&dest, &socksize);
while(1)
{
    /*consocket = accept(mysocket, (struct sockaddr *)&dest, &socksize);*/
    printf("Incoming connection from %s - sending welcome\n", inet_ntoa(dest.sin_addr));
    printf("\n\nClient Connected,\n\nFile Send Successfully\n\n");
    FILE* fp = fopen("server.txt","r");
    while(!feof(fp))
    {

        bzero(buf,sizeof(buf));
        fread(buf,sizeof(char),50,fp);
        write(consocket,buf,50);
    }
    write(consocket ,"quit1234",50);
    fclose(fp);
    return 0;
}
}

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

#define MAXRCVLEN 500
#define PORTNUM 1995

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

    int mysocket,n;
    struct sockaddr_in dest;
    mysocket = socket(AF_INET, SOCK_STREAM, 0);
    memset(&dest, 0, sizeof(dest));
    dest.sin_family = AF_INET;
    dest.sin_addr.s_addr = inet_addr("127.0.0.1");
    dest.sin_port = htons(PORTNUM);
    connect(mysocket, (struct sockaddr *)&dest, sizeof(struct sockaddr));
    printf("\n\n CLIENT CONNECTED\n\nFile Received Successfully...\n\n");
    char buf[50];
    FILE* fp = fopen("client.txt","w");
    while(1)
         {
             bzero(buf,sizeof(buf));
             read(mysocket,buf,50);
             if(strcmp(buf,"quit1234")==0)
                {
                break;
                }
             fprintf(fp,"%s",buf);
        }

    fclose(fp);
}

static const char filename[] = "file.txt";
FILE *file = fopen ( filename, "r" );
if ( file != NULL )
{
char line [ 128 ]; /* or other suitable maximum line size */
   
while ( fgets ( line, sizeof line, file ) != NULL ) /* read a line */
  {
  fputs ( line, stdout ); /* write the line */
  }
fclose ( file );
}
else
{
perror ( filename ); /* why didn't the file open? */
}
return 0;
}