Linux网络编程实现客户端服务端收发数据功能

客户端代码

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

int main(void)
{
int st = socket(AF_INET, SOCK_STREAM, 0);//初始化socket

struct sockaddr_in addr; // 定义一个IP地址的结构
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;// 设置结构地址类型为TCP/IP地址
addr.sin_port = htons(8080); // 制定一个端口号：8080，htons：将short类型从host字节类型转到net字节类型
// 将字符类型的IP地址转化为int，赋给addr结构
//addr.sin_addr.s_addr = inet_addr("127.0.0.1");
addr.sin_addr.s_addr = inet_addr("192.168.10.210");

//
if (connect(st, (struct sockaddr *)&addr, sizeof(addr)) == -1)
{
printf("connect failed %s\n", strerror(errno));
return EXIT_FAILURE;
}

char s[1024];
memset(s, 0, sizeof(1024));
strcpy(s, "hello world");

if (send(st, s, strlen(s), 0) == -1)
{
printf("send failed %s\n", strerror(errno));
}
//sleep(100);
close(st);

return EXIT_SUCCESS;
}


服务端代码
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

int main(int arg, char *args[])
{
int st = socket(AF_INET, SOCK_STREAM, 0); //初始化socket

int on = 1;
if (setsockopt(st, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
{
printf("setsockopt failed %s\n", strerror(errno));
return EXIT_FAILURE;
}

struct sockaddr_in addr; // 定义一个IP地址结构
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET; // 将addr结构的属性定位为TCP/IP地址
addr.sin_port = htons(8080); // 将本地字节顺序转化为网络字节顺序
addr.sin_addr.s_addr = htonl(INADDR_ANY); // INADDR_ANY代表这个server上所有的地址

// 将ip与server程序绑定
if (bind(st, (struct sockaddr *) &addr, sizeof(addr)) == -1)
{
printf("bind failed %s\n", strerror(errno));
return EXIT_FAILURE;
}

// server端开始listen
if (listen(st, 20) == -1)
{
printf("listen failed %s\n", strerror(errno));
return EXIT_FAILURE;
}
//printf("listen success\n");
char s[1024];
int client_st = 0;
struct sockaddr_in client_addr; // 表示client端的IP地址
int i;
for (i = 0; i < 5; i++)
{
memset(&client_addr, 0, sizeof(client_addr));
socklen_t len = sizeof(client_addr);
// accept会阻塞，直到有客户端连接过来，accept返回client的socket描述符
client_st = accept(st, (struct sockaddr*) &client_addr, &len);
if (client_st == -1)
{
printf("accept failed %s\n", strerror(errno));
return EXIT_FAILURE;
}

/* 第一个版本
memset(s, 0, sizeof(1024));
if (recv(client_st, s, sizeof(s), 0) == -1)
{
printf("recv failed %s\n", strerror(errno));
close(client_st);
return EXIT_FAILURE;
}
printf("revc is %s\n", s);
close(client_st);*/

// 第二个版

/*while (1)
{
memset(s, 0, sizeof(1024));
if (recv(client_st, s, sizeof(s), 0) > 0)
{
printf("revc is %s\n", s);
} else
{
printf("recv failed %s\n", strerror(errno));
break;
}
}
close(client_st);*/

// 第三个版本
while (1)
{
memset(s, 0, sizeof(1024));
int rc = recv(client_st, s, sizeof(s), 0);// 是阻塞调用
if (rc > 0)
{
printf("revc is %s\n", s);
} else
{
if (rc == 0)
{
printf("client socket closed\n");
}
else
{
printf("recv failed %s\n", strerror(errno));
}
break;
}
}
close(client_st);

}
close(st);
return 0;
}

makefile文件内容
.SUFFIXES:.c .o

CC=gcc
SRCS1=sock.c
SRCS2=server.c

OBJS1=$(SRCS1:.c=.o)
OBJS2=$(SRCS2:.c=.o)
EXEC1=client
EXEC2=server

all: $(OBJS1) $(OBJS2)
$(CC) -o $(EXEC1) $(OBJS1)
$(CC) -o $(EXEC2) $(OBJS2)
@echo '----------------ok------------'

.c.o:
$(CC) -Wall -g -o $@ -c $<

clean:
rm -f $(OBJS1)
rm -f core*