socket 파일 전송 서버

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


void error(const char *msg){
perror(msg);
exit(1);
}

int main(int argc, char *argv[])
{
int sockfd, newsockfd, port_number;
socklen_t clilen;
char buffer[1024];
struct sockaddr_in serv_addr, cli_addr;
int n;
if (argc < 2) {
fprintf(stderr,"ERROR, no port provided\n");
exit(1);
}
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
error("ERROR opening socket");
bzero((char *) &serv_addr, sizeof(serv_addr));
port_number = atoi(argv[1]);
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(port_number);
if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
error("ERROR on binding");
listen(sockfd, 5);
clilen = sizeof(cli_addr);
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);
if (newsockfd < 0)
error("ERROR on accept");

FILE *fp;
int ch = 0;
fp = fopen("Hean_receive.txt","a");
int words;
read(newsockfd, &words, sizeof(int));
//printf("Passed integer is : %d\n" , words);      //Ignore , Line for Testing
while(ch != words){
read(newsockfd, buffer, 1024);
fprintf(fp, " %s", buffer);
//printf(" %s %d "  , buffer , ch); //Line for Testing , Ignore
ch++;
}
printf("The file was received successfully\n");
printf("The new file created is Korea_HeaNam Full Name");
close(newsockfd);
close(sockfd);
return 0;
}

// compile: gcc -o server server.c
// ./server 9999