socket简单通信

粗糙简略的初版，后续多加点功能权当练手

/*
============================================================================
Name : server.c
Author : king
Version :
Copyright : Your copyright notice
Description : Hello World in C, Ansi-style
============================================================================
*/
#include <stdlib.h>
#include <pthread.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h> /* inet(3) functions */

#include <stdlib.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>

int handle(int point);

int main(void) {
int sfd, ind;
struct sockaddr_in addr;
struct sockaddr_in clent;
char resv[1024], sendbuf[1024];
char buf[1024];
char * myaddr = "192.168.231.128";

int ret; // 返回值设置
socklen_t lent;
int pid;
addr.sin_family = AF_INET; //IPv4 Internet protocols

addr.sin_port = htons(5050); //这里输入服务器端口号

addr.sin_addr.s_addr = inet_addr(myaddr);
; //INADDR_ANY表示本机IP

//獲取socket描述符，IPV4asd
printf("socket start 
");
sfd = socket(AF_INET, SOCK_STREAM, 0);

if (sfd < 0) {
printf("socket error 
");
return -1;
}
printf("bind start 
");
//将套接子与指定端口链接
if (bind(sfd, (struct sockaddr *) &addr, sizeof(struct sockaddr)) < 0) {
printf("bind error 
");
return -1;
}

//监听套接子
printf("listen start 
");
if (listen(sfd, 1024) < 0) {
printf("listen error 
");
return -1;
}

for (;;) {
//接受来自客户端的信息
printf("accept start 
");
memset(&clent, 0, sizeof(clent));
lent = sizeof(clent);
ind = accept(sfd, (struct sockaddr *) &clent, &lent);
if (ind < 0) {
printf("accept error %d 
", ind);
return -1;
}

printf("infor 
");
printf("clent addr%s porit %d
",
inet_ntop(AF_INET, &clent.sin_addr, buf, sizeof(buf)),
ntohs(clent.sin_port));

pid = fork();

if (pid == 0) {
//子进程
close(sfd);
handle(ind);
} else if (pid < 0) {
//error
close(ind);
} else {
//父进程
}
}

return EXIT_SUCCESS;

}

int handle(int point) {

int retn;
char buf[1024];

for (;;) {
retn = read(point, buf, sizeof(buf));
if (retn < 0) {
printf("read error 
");
close(point);
break;
} else if (retn == 0) {
printf("client exit 
");
close(point);
break;
}

printf("client:%s
", buf);

if (strcmp("exit", buf) == 0) {
printf("exit 
");
close(point);
return 0;
}
}
return 0;
}

/*
 ============================================================================
 Name        : client.c
 Author      : king
 Version     :
 Copyright   : Your copyright notice
 Description : Hello World in C, Ansi-style
 ============================================================================
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include  <netinet/in.h>
#include  <arpa/inet.h>       /* inet(3) functions */

int handle(int fd);

int main(void) {

    int nsd;
    char buf[1024];

    char * myaddr = "192.168.231.128";
    struct sockaddr_in addr;

    printf("welcome to echo client
");
    nsd = socket(AF_INET, SOCK_STREAM, 0);
    printf("connect start1 
");
    //bzero(addr, sizeof(*addr));
    memset(&addr,0,sizeof(addr));
    printf("connect start2 
");
    addr.sin_family = AF_INET;
    addr.sin_port = htons(5050);
    addr.sin_addr.s_addr=inet_addr(myaddr);


    printf("connect start3 
");
    if (connect(nsd, (struct sockaddr *)&addr, sizeof(struct sockaddr)) < 0) {
        printf("connect error 
");
        return -1;
    }

    sleep(5);
    printf("handle start
");
    handle(nsd);
    close(nsd);
    return EXIT_SUCCESS;
}

int handle(int fd) {

    char sendl[1024], rev[1024];

    int retn;

    for (;;) {

        memset(sendl,0,sizeof(sendl));
        memset(rev,0,sizeof(rev));
        if (fgets(sendl, 1024, stdin) == NULL) {
            break;
        }
        //
        printf("wirte start
");
        write(fd, sendl, strlen(sendl));
        read(fd, rev,strlen(rev));

    }

    return 0;
}

虽然写程序写了好几年，感觉还是技术不过关，于是把socket从新复习了下，
期间遇到错误一直没有编译过去：
connect和accept
因为没有深刻了解这两函数的参数，所以酿成打错

int connect(int sockfd, const struct sockaddr *addr,
socklen_t addrlen);

记住一定是值 addrlen

accept   socklen_t *addrlen要是一个指针

这俩个郁闷死我了，我以为是一样的，结果调了1小时。

还需努力啊。