TCP client

client.c

/* -*- compile-command: "gcc -Wall -pedantic -g3 client.c -o client" -*- */

/**
   TCP client implementation

   1. Create TCP socket.
   2. connect() Connect newly created client socket to server.
**/

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

#define BUFF_SIZE 1000
#define PORT 8080

void func_client(int sockfd)
{
	char buff[BUFF_SIZE];
	int n, nread = 0, nwrite = 0;

    /* infinite loop */
	for (;;) {

		memset(buff, 0, sizeof(buff));
		printf("\nEnter the string : ");
		n = 0;
		while((buff[n++] = getchar()) != '\n');

        errno = 0;
        nwrite = write(sockfd, buff, sizeof(buff));
        if(nwrite == -1) {
            perror("write");
            exit(EXIT_FAILURE);
        }

	    memset(buff, 0, sizeof(buff));
        errno = 0;
		nread = read(sockfd, buff, sizeof(buff));
        if(nread == -1) {
            perror("read");
            exit(EXIT_FAILURE);
        }

		printf("Message From Server : %s\n", buff);
	}
}

// MAIN
int main(int argc, char *argv[])
{
	struct sockaddr_in servaddr;
	int sockfd;

	// Socket create
	sockfd = socket(AF_INET, SOCK_STREAM, 0);
	if(sockfd == -1) {
		printf("Socket creation failed...\n");
		exit(EXIT_FAILURE);
	} else {
		printf("Socket successfully created..\n");
    }

	memset(&servaddr, 0, sizeof(servaddr));

	// Assign IP, PORT
	servaddr.sin_family = AF_INET;
	servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
	servaddr.sin_port = htons(PORT);

	// Connect the client socket to server socket
	if (connect(sockfd, (struct sockaddr*) &servaddr, sizeof(servaddr)) != 0) {
		printf("Client connect() with server failed...\n");
		exit(EXIT_FAILURE);
	} else {
		printf("Connected to the server..\n");
    }

	// Function for CLIENT
	func_client(sockfd);

	// Close the socket
	close(sockfd);

    return 0;
}