Client-Server application to have a server display the contents of a file

Client
 
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h> /* close */
 
#define SERVER_PORT 3080
#define MAX_MSG 100
#define MAX_LINE 900
 
#define ERROR 1
 
int main (int argc, char *argv[]) {
  int sd, rc, i, numLines;
  struct sockaddr_in servAddr;
 
  FILE *fp = NULL;
  char line[MAX_MSG];
 
  if(argc < 3)
  {
    printf("usage: %s <IPAddr> <data1> <data2> ... <dataN>\n",argv[0]);
    exit(1);
  }
 
  /* create socket */
  if ( (sd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
  {
    perror("cannot open socket ");
    exit(1);
  }
 
  /* initialization of sockaddress_in structure */
  servAddr.sin_family = AF_INET;
  servAddr.sin_port = htons(SERVER_PORT);
  if (inet_pton (AF_INET, argv[1], &servAddr.sin_addr) <= 0)
  {
    perror("inet_pton error");
    exit(1);
  }
 
  /* connect to server */
  if (connect(sd, (struct sockaddr *) &servAddr, sizeof(servAddr)) < 0)
  {
    perror("cannot connect ");
    exit(1);
  }
 
  if ((fp = fopen(argv[2], "r")) == NULL)
        {
        printf("ERROR:  Can't open file for reading\n");
        close(sd);
        return ERROR;
        }
  else
        {
        numLines = 0;
        while (fgets(line, MAX_LINE, fp) != NULL)
        {
                if (write(sd, line, strlen(line)) < 0)
                {
                        perror("cannot send data ");
                        close(sd);
                        return ERROR;
                }
                numLines++;
        }
        printf("File %s has been sent (%d lines)\n", argv[2], numLines);
        fclose(fp);
        close(sd);
 
}
 
 
 
return 0;
 
}
 
 
Server
 
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h> /* close */
 
#define SUCCESS 0
#define ERROR 1
 
#define END_LINE 0x0A
#define SERVER_PORT 3080
#define MAX_MSG 100
 
int main (int argc, char *argv[])
{
  int sd, newSd, cliLen;
  ssize_t nread, count;
  pid_t pid;
 
  struct sockaddr_in cliAddr, servAddr;
  char line[MAX_MSG];
 
     /* create socket */
  if ( (sd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
 
  {
    perror("cannot open socket ");
    return ERROR;
  }
 
  /* bind server port */
  servAddr.sin_family = AF_INET;
  servAddr.sin_addr.s_addr = htonl(INADDR_ANY);
  servAddr.sin_port = htons(SERVER_PORT);
  if(bind(sd, (struct sockaddr *) &servAddr, sizeof(servAddr))<0)
  {
    perror("cannot bind port ");
    return ERROR;
  }
 
  /* begin listening on the socket */
  listen(sd,5);
 
  while(1)
  {
    printf("%s: waiting for data on port TCP %u\n",argv[0],SERVER_PORT);
    cliLen = sizeof(cliAddr);
    newSd = accept(sd, (struct sockaddr *) &cliAddr, &cliLen);
    if (newSd < 0)
        {
        perror("cannot accept connection ");
        close(sd);
        return ERROR;
      }
        //new code starts here
    else
        {
        //a new child process is created
         if ((pid = fork()) < 0)
        {
                printf("Fork error\n");
                close(newSd);
                exit(1);
        }
        else if (pid == 0) /* child */
        /* initialize line buffer to 0 */
        memset(line, 0x0, MAX_MSG);
        break;
        }
 
  line[count++] = ',';
  line[count++] = ' ';
 
  } /* while (1) */
 
}

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