我的c程序

想写一个不同机器通信获取状态的c程序。遇到无数困难。断断续续了3、4周了，得到的结果仍然无法面世。 我想还是把其中遇到的所有困难写下来吧！

下面是结果

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <netdb.h>
#define SERV_PORT 1113
#define LISTENQ  32
#define MAXLINE 1024
#define MAX_LINE 200
/***连接处理函数***/
void sendMSG2Client(int fd);
int isUsing = 0; // 0没使用  1正在被使用
char *who;
char *productName;
char* productVersion;
char *path;
char *setupMode;
char *dbType;

void split(char arr[], char *arr2[], const char *del) {
	int i = 0;
	printf("arr %s\n",arr);

	char *s = strtok(arr, "=");
	while(s != NULL) {
	    arr2[i++] = s;
		printf("arr2 i  %s\n",arr2[i]);
	    s = strtok(NULL, "=");
	}
	//return arr2;
}

int readsystemcfgfile( char* filename )
{
    FILE* fp;
    char buffer[15];
    fp = fopen(filename, "r");
    if (fp == NULL) {
        perror("File open error");
        exit(1);
    }
	char *arr[2];
    while (fgets(buffer, MAX_LINE, fp) != NULL) {
		printf("buffer is  %sqqq\n",buffer);

    }
	printf("aa %s",arr[1]);
    return 0;
}

/*截取src字符串中,从下标为start开始到end-1(end前面)的字符串保存在dest中(下标从0开始)*/
char *substring(char *src,int start,int end)
{
	printf("The buf is : %s\n" , src);
	int ss = 0;
	for ( ss=0 ; ss<strlen(src); ss++) {
		printf("%c",src[ss]);
	}
	char *dest;
	char *p=src;
	int i = start;
	if(start>strlen(src))return;
	if(end>strlen(src))
		end=strlen(src);
	while(i<end)
	{
		dest[i-start]=src[i];
		printf("%c",src[i]);
		i++;
	}
	dest[i-start]='\0';
	printf("\nThe dest is : %s\n" , dest);
	return dest;
}

int readVersionfile( char* filename )
{
    FILE* fp;
    char buffer[MAX_LINE];
	//char* productVersion;

 	filename[180] = "/opt/luo/c/test";
	char *prodversionfile = strcat( filename, "/etc/version.xml");
    fp = fopen(filename, "r");
    if (fp == NULL) {
        perror("File open error");
        exit(1);
    }
    while (fgets(buffer, MAX_LINE, fp) != NULL) {
		fputs(buffer, stdout);
		char *start = strstr(buffer,"PLATFORM_VERSION");
		printf("start %s " , start);
		if ( start != NULL) {
			char *end = strstr(buffer,"</param>");
			if(end == NULL ) { printf(" not he liee\n");
				continue;
			}
			printf("end %s " , end);
			productVersion  = substring(buffer,33,50);
		}
    }
	printf("productVersion is : %s",productVersion);
    return 0;
}

void sendMSG2Client(int sockfd){
	ssize_t n;
    char  buf[MAXLINE];
	fprintf(stdout,"bbbb 4444  \n");
    again:
    while ( (n = read(sockfd, buf, MAXLINE)) > 0) {
		printf(" buf is   : %s\n" , buf);
		if( strstr(buf, "showStatus") ){// 查看
				printf(" showStatus  = : %s\n", buf);
				//write(sockfd, isUsing, 2);
				readsystemcfgfile("/opt/openssh/mytest.cfg");
				readVersionfile("/opt/openssh/mytest.cfg");
				char destination[75];
				strcat(destination,productName);
				strcat(destination,path);
				strcat(destination,productVersion);
				strcat(destination,who);
				write(sockfd, destination, sizeof(destination));
		}else if (  strcmp("register",buf)==0 ) {//注册
			printf("register !");
			isUsing = 1;
			who=buf;
			write(sockfd, "Register success!", n);
			printf("Register success!");
		} else if ( strcmp("unregister",buf)==0 ) {//取消注册
			who = NULL;
			printf("unregister !");
			isUsing = 0;
			write(sockfd, "Unregister success!", strlen("Unregister success!"));
		}
		break;
	}
    if (n < 0 && errno == EINTR)//被中断，重入
        goto again;
    else if (n < 0){//出错
		fprintf(stderr,"read error:%s\n\a",strerror(errno)); //  fprintf  ??
		exit(1);
    }
}

int main(int argc, char *argv[]){
// printf失效？
// strcat("Hi! I am " , ip_search()) ___ 这里却不报错。。。 怎么异常捕捉？ write(sockfd, strcat("Hi! I am " , ip_search()), 10);
  int listenfd,connfd;
  pid_t childpid;
  socklen_t clilen;
  struct sockaddr_in servaddr;
  struct sockaddr_in cliaddr;
  if((listenfd = socket(AF_INET, SOCK_STREAM,0))==-1){
     fprintf(stderr,"Socket error:%s\n\a",strerror(errno));
     exit(1);
  }
  /* 服务器端填充 sockaddr结构*/
  bzero(&servaddr, sizeof(servaddr));
  servaddr.sin_family = AF_INET;
  servaddr.sin_addr.s_addr = htonl (INADDR_ANY);
  servaddr.sin_port = htons(SERV_PORT);
  /* 捆绑listenfd描述符  */
  if(bind(listenfd,(struct sockaddr*)(&servaddr),sizeof(struct sockaddr))==-1){
    fprintf(stderr,"Bind error:%s\n\a",strerror(errno));
    exit(1);
   }
   /* 监听listenfd描述符*/
    if(listen(listenfd,5)==-1){
        fprintf(stderr,"Listen error:%s\n\a",strerror(errno));
        exit(1);
    }
    for ( ; ; )  {
		clilen = sizeof(cliaddr);
		/* 服务器阻塞,直到客户程序建立连接  */
		if((connfd=accept(listenfd,(struct sockaddr*)(&cliaddr),&clilen))==-1){
			fprintf(stderr,"Accept error:%s\n\a",strerror(errno));
			exit(1);
		}
		fprintf(stdout,"aaa \n");
		//有客户端建立了连接后
		if ( (childpid = fork()) == 0) { /*子进程*/
			fprintf(stdout,"bbbb 1 \n");
			close(listenfd);    /* 关闭监听套接字*/
			fprintf(stdout,"bbbb 2 \n");
			sendMSG2Client(connfd);   /*处理该客户端的请求*/
			fprintf(stdout,"bbbb 3 \n");
			exit (0);
		}
		close(connfd);/*父进程关闭连接套接字，继续等待其他连接的到来*/
	}
}

　　asd

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <netdb.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <time.h>

#define SERV_PORT 1113
#define MAXLINE 1024
#define LISTENQ  32
#define ERRORIP "cannot find host ip"

char* sendMSG2Server(FILE *fp, char *cmd, char *ipaddr);
char* servaddrs[] = {"10.xx.xx.118","10.xx.xx.117","10.xx.xx.116"};
char *ip_search(void);

// 第一个参数，操作类型，第二个参数ip，若ip为空，则register/unregister当前
int main(int argc, char **argv)
 {
	char* ipaddr;
	char* ret;
	printf("argsss : %d" , argc);
    if ( argc < 2 || argc > 3){
        fprintf(stderr,"Param error ! usage: operation <IPaddress>\n\a");
        exit(0);
    }

	printf("ffff cmd : $s",argv);

	//	if (argv[1] == "showAllStatus") {dd//查看所有showAll
	if( strcmp(argv[1], "showAllStatus")==0 ){
		int eng = 2;//servaddrs.length;
		int i;
		for(i=0;i<eng;i++) {
			ret = strcat(ret, sendMSG2Server( NULL, "showStatus", servaddrs[i]) );
		}
	} else {
		printf("ip_search i is : %s \n",ip_search());
		if( argc == 2) {
				ipaddr = ip_search();
		} else {
			ipaddr = argv[2];
		}
		printf("Client ip is : %s", ipaddr);
		ret = sendMSG2Server(stdin, argv[1], ipaddr);
	}
	 printf(ret);
     exit(0);
 }

 // 进行服务端的操作
char* sendMSG2Server(FILE *fp, char *cmd, char *ipaddr)
{
   int nbytes=0;
   int     sockfd;
   struct sockaddr_in servaddr;
   char recvline[MAXLINE];
	if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1){
        fprintf(stderr,"Socket error:%s\n\a",strerror(errno));
        exit(1);
    }
	/* 客户程序填充服务端的资料*/
      bzero(&servaddr,sizeof(servaddr));
      servaddr.sin_family=AF_INET;
      servaddr.sin_port=htons(SERV_PORT);
	  if (inet_pton(AF_INET, ipaddr, &servaddr.sin_addr) <= 0){
            fprintf(stderr,"inet_pton Error:%s\a\n",strerror(errno));
            exit(1);
	  }
   	  /* 客户程序发起连接请求*/
      if(connect(sockfd,(struct sockaddr *)(&servaddr),sizeof(struct sockaddr))==-1){
            fprintf(stderr,"connect Error:%s\a\n",strerror(errno));
            exit(1);
      }
	if( strcmp(cmd,"showStatus")==0 ){// 查看 showStatusa
		printf("aaaaaa shhh \n ");
		write(sockfd, "showStatus", strlen("showStatus"));		//wirte信息应该包括： 操作类型、操作人、日期、参数可以不需要
	} else if (cmd == "register") {//注册
		write(sockfd, "register", strlen("register"));
	} else if (cmd == "unregister") {//取消注册
		write(sockfd, "unregister", strlen("unregister"));
	}
	fprintf(stdout,"AAAAAAAA \n");
	if ((nbytes=read(sockfd, recvline, MAXLINE)) == 0){//从sockfd读取从服务器发来的数据
	  fprintf(stderr,"sendMSG2Server: server terminated prematurely\n");
	  exit(1);
	}
	fprintf(stdout,"bbbb \n");
	recvline[nbytes]='\0';
	fprintf(stdout,"cc \n");
	fputs(recvline, stdout);
	return recvline;
}

// 获取客户端 ip-- shell客户端ip    ....   当前机器ip ？ no
char *ip_search(void)
{
    int sfd, intr;
    struct ifreq buf[16];
    struct ifconf ifc;
    sfd = socket (AF_INET, SOCK_DGRAM, 0);
    if (sfd < 0)
        return ERRORIP;
    ifc.ifc_len = sizeof(buf);
    ifc.ifc_buf = (caddr_t)buf;
    if (ioctl(sfd, SIOCGIFCONF, (char *)&ifc))
        return ERRORIP;
    intr = ifc.ifc_len / sizeof(struct ifreq);
    while (intr-- > 0 && ioctl(sfd, SIOCGIFADDR, (char *)&buf[intr]));
    close(sfd);
    return inet_ntoa(((struct sockaddr_in*)(&buf[intr].ifr_addr))-> sin_addr);
}

　　

真是搞不懂，竟然在这个循环里面卡住了。

fp文件里面有三行，

    while (fgets(buffer, MAX_LINE, fp) != NULL) {
		printf("buffer is  %sqqq\n",buffer);

    }

。。
待续。。

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <netdb.h>
#define SERV_PORT 1113
#define LISTENQ  32
#define MAXLINE 1024
#define MAX_LINE 200
#define ARRLEN(arr) (sizeof(arr)/sizeof(arr[0]))
/***连接处理函数***/
void sendMSG2Client(int fd);
int isUsing = 0; // 0没使用  1正在被使用
char *who;
char *productName;
char productVersion[20];
char *productPath;
char *setupMode;
char *dbType;

void split(char src[], char *dest[], const char *del) {
	int i = 0;
	char *s = strtok(src, del);
	while(s != NULL) {
	    dest[i++] = s;
	    s = strtok(NULL, del);
	}
}

int readsystemcfgfile(  )
{
    FILE* fp;
    char *filename = "/opt/openssh/system.cfg";
    char buffer[50];
    fp = fopen(filename, "r");
    if (fp == NULL) {
        perror("File open error");
        exit(1);
    }
    char *systemcfgArr[2] ;
    while (fgets(buffer, MAX_LINE, fp) != NULL) {
		if ( !strstr(buffer, "=" ) ) {
			continue;
		}
		split(buffer, systemcfgArr, "=");
    }
	productName = systemcfgArr[0];
	productPath = systemcfgArr[1];
	int i;
	for(i=0;i<strlen(productName);i++) {
		//printf(" x  = : %c\n", productName[i]);
	}
	for(i=0;i<strlen(productPath) && productPath[i] != '\n' && productPath[i] != '\r' ;i++) {
		//printf(" y  = : %c\n", productPath[i]);
	}
    return 0;
}

void substring(char *src,char *dest,int start,int end)
{
    int i=start;
    if(start>strlen(src))return;
    if(end>strlen(src))
        end=strlen(src);
    while(i<end)
    {
        dest[i-start]=src[i];
        i++;
    }
    dest[i-start]='\0';
    return;
}

int readVersionfile( char* filepath )
{
    FILE* fp;
    char buffer[MAX_LINE];
	//char* productVersion;
// 	filepath[180] = "/opt/iEMP/iEMP";
	char prodversionfile[100];
	strcat( prodversionfile,filepath);
	strcat( prodversionfile, "/etc/platformversion.xml");
    fp = fopen(prodversionfile, "r");
    if (fp == NULL) {
        perror("File open error");
        exit(1);
    }
    while (fgets(buffer, MAX_LINE, fp) != NULL) {
		//fputs(buffer, stdout);
		//printf(" version file  = : %s\n", buffer);
		char *start = strstr(buffer,"PLATFORM_VERSION");
		//printf("start %s " , start);
		if ( start != NULL) {
			char *end = strstr(buffer,"</param>");
			if(end == NULL ) {
				continue;
			}
			//char xx[] = "abcdefghijklmnopqrstuvwxyz123456789";
			substring( buffer, productVersion , 33,59);
			//printf("end productVersion %s \n" ,productVersion);
			//return 0;
			break;
		}
    }
	//printf("productVersion is : %s",productVersion);
    return 0;
}

void sendMSG2Client(int sockfd){
	ssize_t n;
    char  buf[MAXLINE];
			char *registerInfo[2];
    //fprintf(stdout,"bbbb 4444  \n");
    again:
    while ( (n = read(sockfd, buf, MAXLINE)) > 0) {
		//printf(" buf is   : %s\n" , buf);
		int i;
		for(i=0;i<strlen(buf);i++) {
			//printf(" buf x  = : %c\n", buf[i]);
		}

		if( strstr(buf, "showStatus") ){// 查看
				//printf(" showStatus  = : %s\n", buf);
				//write(sockfd, isUsing, 2);
				readsystemcfgfile();
				char destination[100] = "";
				char productNameArr[10] = "";
				char productPathArr[20] = "";
				int i;
				for(i=0;i<strlen(productName);i++) {
					productNameArr[i] = productName[i];
				}
				for( i=0;i<strlen(productPath);i++) {
					if( productPath[i] != '\n' && productPath[i] != '\r' ) productPathArr[i] = productPath[i];
				}
				readVersionfile(productPathArr);
				//printf(" who   : %s\n" , who);
				if( who==NULL) {
					who = "NO ONE";
				}
				sprintf(destination, "%10s%15s%30s%45s\n", who, productNameArr , productPathArr , productVersion);
				//printf(destination);
				write(sockfd, destination, sizeof(destination)/sizeof(destination[0]));

				productName = "iemppppp";
				//strcat(productVersion,productPath);
				//char *pv =
				//strcat(productVersion, productName);
		} else if (strstr(buf, "register")) {//注册
			printf("register rr : %s !\n", buf);
			//printf(" aaaa ");
			char src[MAXLINE];
			//printf(" bbb ");
			for(i=0;i<strlen(buf) && buf[i] != '\0' && buf[i] != '\r';i++) {
				//printf(" aasdfff ");
				src[i] = buf[i];
			}
			//printf(" aasdfff ");
			split(src, registerInfo, ",");
			char *opt = registerInfo[1];
			char *whoaa;
			for(i=0;i<8 && registerInfo[1][i] != '\0' && registerInfo[1][i] != ' ';i++) {
				//printf("/%c ", registerInfo[1][i]);
				whoaa[i] = registerInfo[1][i];
			}
			who = whoaa;//当前函数退出后， lk 也会被回收吗？？
			isUsing = 1;
			write(sockfd, "Register success!", n);
		} else if (strstr(buf, "unregister")) {//取消注册
			who = NULL;
			printf("unregister !");
			isUsing = 0;
			write(sockfd, "Unregister success!", strlen("Unregister success!"));
		}
		break;
	}
    if (n < 0 && errno == EINTR)//被中断，重入
        goto again;
    else if (n < 0){//出错
		fprintf(stderr,"read error:%s\n\a",strerror(errno)); //  fprintf  ??
		exit(1);
    }
}

int mainaa(int argc,char * agrs[]) {

char destination[50] = "succc";
//strcat(destination,"luo");
printf(" ****straa****  %s\n", destination);

char buf[] = "asfdafregister,lk";
if (strstr(buf, "register")) {

	printf(" ****xx****  %s\n", destination);
}

}

int main(int argc, char *argv[]){
// printf失效？
// strcat("Hi! I am " , ip_search()) ___ 这里却不报错。。。 怎么异常捕捉？ write(sockfd, strcat("Hi! I am " , ip_search()), 10);
  int listenfd,connfd;
  pid_t childpid;
  socklen_t clilen;
  struct sockaddr_in servaddr;
  struct sockaddr_in cliaddr;
  if((listenfd = socket(AF_INET, SOCK_STREAM,0))==-1){
     fprintf(stderr,"Socket error:%s\n\a",strerror(errno));
     exit(1);
  }
  /* 服务器端填充 sockaddr结构*/
  bzero(&servaddr, sizeof(servaddr));
  servaddr.sin_family = AF_INET;
  servaddr.sin_addr.s_addr = htonl (INADDR_ANY);
  servaddr.sin_port = htons(SERV_PORT);
  /* 捆绑listenfd描述符  */
  if(bind(listenfd,(struct sockaddr*)(&servaddr),sizeof(struct sockaddr))==-1){
    fprintf(stderr,"Bind error:%s\n\a",strerror(errno));
    exit(1);
   }
   /* 监听listenfd描述符*/
    if(listen(listenfd,5)==-1){
        fprintf(stderr,"Listen error:%s\n\a",strerror(errno));
        exit(1);
    }

    for ( ; ; )  {
		clilen = sizeof(cliaddr);
		/* 服务器阻塞,直到客户程序建立连接  */
		if((connfd=accept(listenfd,(struct sockaddr*)(&cliaddr),&clilen))==-1){
			fprintf(stderr,"Accept error:%s\n\a",strerror(errno));
			exit(1);
		}
		fprintf(stdout,"aaa \n");
		//有客户端建立了连接后
		if ( (childpid = vfork()) == 0) { /*子进程*/
			fprintf(stdout,"bbbb 1 \n");
			close(listenfd);    /* 关闭监听套接字*/
			fprintf(stdout,"bbbb 2 \n");
			sendMSG2Client(connfd);   /*处理该客户端的请求*/
			fprintf(stdout,"bbbb 3 \n");
			_exit (0);
		}
		close(connfd);/*父进程关闭连接套接字，继续等待其他连接的到来*/
	}
}

　　

asd

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <netdb.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <time.h>

#define SERV_PORT 1113
#define MAXLINE 1024
#define LISTENQ  32
#define ERRORIP "cannot find host ip"

char *sendMSG2Server(char **args, char *ipaddr);
char* sendMSG2Server0(char *cmd, char *ipaddr);
char* servaddrsaaa[] = {"10.67.164.218","10.67.164.217","10.67.164.216"};
char* servaddrs[] = {"10.67.164.218","10.67.164.217"};
char *ip_search(void);

// 第一个参数，操作类型，第二个参数ip，若ip为空，则register/unregister当前
int main(int argc, char **argv) {
	char* ipaddr;
	printf("argc : %d\n" , argc);
    if ( argc < 2 || argc > 3){
        fprintf(stderr,"Param error ! usage: operation + <IPaddress>\n\a");
        exit(0);
    }
	printf("argv: $s\n",argv);

	char ret[2000];
	char *retLine;

	if (checkParam(argc, argv) == 0) {
		return -1;
	}

	char destination[100] = "";
	sprintf(destination, "%10s%15s%30s%45s\n", "WHO" ,"product Name" , "product Path" , "product Version");
	printf(destination);

	if( strcmp(argv[1], "sa")==0 ){//查看所有showAll
		int eng = 2;//servaddrs.length;
		int i;
		for(i=0;i<eng;i++) {
			sprintf(retLine, "%15s %s\n",servaddrs[i], sendMSG2Server0("showStatus", servaddrs[i]) );
			strcat(ret,retLine);
		}
		printf(ret);
	} else {
		if( argc >= 2) {
			if(strcmp(argv[1], "r") ==0 || strcmp(argv[1], "u")==0) {
				printf("argv[2] i is : %s \n", argv[2] );
				ipaddr = ip_search();
			} else {
				ipaddr = argv[2];
			}
		}
		printf("Client ip is : %s \n", ipaddr);
		retLine = sendMSG2Server(argv, ipaddr);
		printf(retLine);
	}

	fprintf(stdout,"succ returned \n");

    exit(0);
}

// 1 true; 0 false
int checkParam(int argc, char **argv) {
	if(strcmp(argv[1], "s") !=0 && strcmp(argv[1], "sa")!=0 && strcmp(argv[1], "r")!=0 && strcmp(argv[1], "u")!=0) {
		fprintf(stderr,"Param error ! usage: showAllStatus \n\a");
		return 0;
	}
	if( strcmp(argv[1], "sa")==0 ){		//查看所有showAll
		if( argc > 2) {
			fprintf(stderr,"Param error ! usage: showAllStatus \n\a");
			return 0;
		}
	} else {

	}

	return 1;
}
char * sendMSG2Server(char **argv, char *ipaddr) {
	char cmd[20];
	char *opt = argv[1];
	char *who;
	//strcat(cmd, opt);
	if (strcmp(opt, "s") ==0){// 查看 showStatus
		return sendMSG2Server0("showStatus", ipaddr);//   			wirte信息应该包括： 操作类型、操作人、日期、参数可以不需要
	} else if(strcmp(opt, "r") ==0) {//注册
		/*if( argc != 3) {
			fprintf(stderr,"Param error ! ");
		}*/
		//who = argv[2];
		//strcat(cmd, who);
		sprintf(cmd, "%s,%s", "register",argv[2]);
		return sendMSG2Server0(cmd, ipaddr);
	} else if (strcmp(opt, "unregister") == 0) {//取消注册
		return sendMSG2Server0("unregister", ipaddr);
	}
}

char* sendMSG2Server110(char *cmd, char *ipaddr) {
	printf("aaaaaa %s\n", cmd);
	return "";
}

 // 进行服务端的操作
char* sendMSG2Server0(char *cmd, char *ipaddr) {
	int nbytes=0;
	int sockfd;
	struct sockaddr_in servaddr;
	char recvline[MAXLINE];
	if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1){
        fprintf(stderr,"Socket error:%s\n\a",strerror(errno));
        exit(1);
    }
	/* 客户程序填充服务端的资料*/
	bzero(&servaddr,sizeof(servaddr));
	servaddr.sin_family=AF_INET;
	servaddr.sin_port=htons(SERV_PORT);
	if (inet_pton(AF_INET, ipaddr, &servaddr.sin_addr) <= 0){
		fprintf(stderr,"inet_pton Error:%s\a\n",strerror(errno));
		exit(1);
	}
	/* 客户程序发起连接请求*/
	if(connect(sockfd,(struct sockaddr *)(&servaddr),sizeof(struct sockaddr))==-1){
		fprintf(stderr,"connect Error:%s\a\n",strerror(errno));
		exit(1);
	}
	write(sockfd, cmd, strlen(cmd));
	if ((nbytes=read(sockfd, recvline, MAXLINE)) == 0){//从sockfd读取从服务器发来的数据
		fprintf(stderr,"sendMSG2Server: server terminated prematurely\n");
		exit(1);
	}
	recvline[nbytes]='\0';
	//fputs(recvline, stdout);
	return recvline;
}

// 获取客户端 ip-- shell客户端ip    ....   当前机器ip ？ no
char *ip_search(void) {
    int sfd, intr;
    struct ifreq buf[16];
    struct ifconf ifc;
    sfd = socket (AF_INET, SOCK_DGRAM, 0);
    if (sfd < 0)
        return ERRORIP;
    ifc.ifc_len = sizeof(buf);
    ifc.ifc_buf = (caddr_t)buf;
    if (ioctl(sfd, SIOCGIFCONF, (char *)&ifc))
        return ERRORIP;
    intr = ifc.ifc_len / sizeof(struct ifreq);
    while (intr-- > 0 && ioctl(sfd, SIOCGIFADDR, (char *)&buf[intr]));
    close(sfd);
    return inet_ntoa(((struct sockaddr_in*)(&buf[intr].ifr_addr))-> sin_addr);
}