About Linux Networking Programming - linux

Question

i have written the client and server c file to make an echo server program,i wrote it according to the tutorial video, but i can not figure out where i made the mistakes
//this is the client.c
#include <sys/socket.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <errno.h>
#include <arpa/inet.h>
int main(void)
{
int sock;
if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
printf("socket establish fail!");
struct sockaddr_in servaddr;
memset(&servaddr, 0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(30000);
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
if(connect(sock, (struct sockaddr*)&servaddr, sizeof(servaddr))<0)
printf("connect failed");
char sendbuf[1024] = { 0 };
char recvbuf[1024] = { 0 };
while (fgets(sendbuf,sizeof(sendbuf),stdin) != NULL)
{
write(sock, sendbuf, sizeof(sendbuf));
read(sock, recvbuf, sizeof(recvbuf));
//fputs(recvbuf, stdout);
printf("%s",recvbuf);
memset(sendbuf, 0, sizeof(sendbuf));
memset(recvbuf, 0, sizeof(recvbuf));
}
close(sock);
return 0;
}
and
//this is the server.c
#include <sys/socket.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <errno.h>
#include <arpa/inet.h>
int main(void)
{
int listenfd, conn;
struct sockaddr_in peeraddr;
struct sockaddr_in servaddr;
socklen_t peerlen = sizeof(peeraddr);
char recvbuf[1024];
if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
printf("socket establish fail!");
memset(&servaddr, 0, sizeof(servaddr));
memset(&recvbuf, 0, sizeof(recvbuf));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(30000);
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
if (bind(listenfd, (struct sockaddr*)&servaddr, sizeof(servaddr)) < 0)
printf("Bind fail");
if (listen(listenfd, 5) < 0)
printf("Listen fail");
if (conn= accept(listenfd, (struct sockaddr*)&peeraddr, &peerlen) < 0)
printf("accept fail");
while (1)
{
int ret = read(conn, recvbuf, sizeof(recvbuf));
//fputs(recvbuf,stdout);
printf("%s",recvbuf);
write(conn, recvbuf, ret);
}
close(conn);
close(listenfd);
return 0;
}
i worked for it for several hours but i can not find the answer
please help me!