Linux網絡編程——SQLite數據庫

學習筆記，小白可以相互學習，大佬看到能告訴咱理解不對的地方就好了。

數據庫基本概念：

1.數據：能夠輸入計算機並能被計算機程序識別和處理的信息集合

2.數據庫：數據庫是在數據庫管理和控制之下，存放在存儲介質上的數據集合

文件管理階段：

優點：1.數據可長期保存 2.能存儲大量數據

缺點：1.數據冗餘度大，數據一致性和完整性難以維持 2.數據與程序缺乏高度獨立性

數據庫系統階段：

1.數據組織結構化  2.數據冗餘度比較小，易擴充 3.具有較高的數據與程序之間的獨立性   4.統一的數據控制

SQLite有以下特性：

1.零配置----無需安裝和管理配置

2.存儲在單一磁盤文件中的一個完整的數據庫

3.數據庫文件可以再不同字節順序的機器間自由共享

4.支持數據庫大小至2TB

5.足夠小，全部源碼大致3萬行c代碼，250kb

6.比目前流行的大多數數據庫對數據的操作要快

SQLite常用命令介紹

顯示所有命令：sqlite->help

  退出sqlite3：sqlite->quit

  顯示當前打開的數據庫文件：sqlite->database

  顯示數據庫中所有的表名：sqlite->.table

  查看錶的結構：sqlite->.schema <table_name>

以下爲SQL命令以；結束

1.創建新表

sqlite->creat table <table_name> (f1 type1,f2 type2,...);

例如：creat table stu(nu Integer,name char,score float);//char 表示字符串，也可用string ，txt

//creat table stu(nu Integer primary key,name char,score float);加了primary key表示nu作爲主鍵，不可重複，不能插入相同主鍵的數據

2.插入（向表中添加新記錄）

insert into <table_name> values(value1,value2,...);

例如：insert into stu values(1,"xiaoli",99)；

3.查詢

selete * from <table_name>；//查詢表中所有記錄，例如selete * from stu;

 按照指定條件查詢：

selete * from <table_name> where <expression>;   

//例如：selete number  * from stu where score>60 and number=1;

//selete number,name from stu where score<60;

4.刪除

delete from <table_name>  where <expression>;//刪除指定記錄

drop table <table_name>;//刪除表

5.修改（更新表中內容）

update <table_name> set <f1=value1> <f2=value2>...where <expression>;

例如：update stu set name="xiaozhang" ,score=100 where number = 3;

6.在表中添加字段（添加一列）

alter table <table_name> add column <filed> <type> default...;//添加

alter table <table_name> drop column<filed>;//刪除一列

例如：alter table stu add column address char；//address是添加的名稱,char是添加的address的類型

7.在表中刪除字段（刪除一列）

sqlite中不允許刪除字段，通過下面的步驟一樣可以達到同樣的目的

creat table stu1 as select number,name,score from stu;//新建一張表stu1同原來一樣

drop table stu;//刪除原表stu

alter table stu1 rename to stu ;//將表stu1重命名爲stu

SQLite編程接口（編譯時gcc sqlite.c -lsqlite3）

int sqlite3_open(char *filename,sqlite 3 **db);

功能：打開sqlite數據庫

filename：數據庫文件名（UTF-8編碼格式）

db：指向sqlite句柄的指針

返回值：成功：0 失敗：返回錯誤碼（非0值）//ret ！=SQLITE_OK判斷否成功返回

int sqlite2_close(sqlite3 *db);

功能：關閉sqlite數據庫

返回值：成功返回0，失敗返回錯誤碼

const char *sqlite3_errmsg(sqlite *db)

功能：存放錯誤信息

返回值：返回錯誤信息

int sqlite3_exec(sqlite3 *db,const char *sql,sqlite3_callback callback,void *,char **errmsg);

功能：執行SQL操作

db：數據庫句柄

sql：SQL語句

callback：回調函數，沒有則爲NULL

errmsg：錯誤信息指針的地址

返回值：成功返回0，石板返回錯誤碼

typedef int(*sqlite3_callback)(void *para,int f_num,char **f_value,char **f_name);

功能：找到每一條記錄自動執行一次回調函數

f_num：記錄中包含的字段數目

f_value：包含每個字段值的指針數組

f_name：包含每個字段名稱的指針數組

返回值：成功0，失敗-1

不使用回調函數執行SQL語句

int sqlite3_get_table(sqlite3 *db,const char *sql,char ***resultp,int *nrow,int ncolumn,char **errmsg);

功能：執行SQL操作

db:數據庫句柄 //打開的數據庫

sql：SQL語句 //要評估的sql

resultp：用來指向sql執行結果的指針 //查詢結果

nrow:滿足條件的記錄的數目 //寫在這裏的結果行號

ncolumn:每條記錄包含的字段數目 //結果列數

errmsg：錯誤信息指針的地址

返回值：成功返回0，失敗返回錯誤碼

/********sqlite.c*********************************/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sqlite3.h>

/*
 * 何時調用callback函數：表中要要查詢的數據的時候；
 * 查詢到有幾條，函數調用幾次；
 */

int callback(void *para, int f_num, char **f_value, char **f_name)	
{
	int i;
	for (i = 0; i < f_num; i++) 
		printf("%s : %s\n", f_name[i], f_value[i]);
	return 0;
}

int main()
{
	int ret;
	sqlite3 *db;
	char *errmsg;
	char sql[128];

	/* 打開數據庫文件 */
	ret = sqlite3_open("my.db", &db);
	if (ret != SQLITE_OK) {
		fprintf(stderr, "open : %s\n", sqlite3_errmsg(db));
		return -1;
	}
#if 0
	/* 創建表 */

	sprintf(sql, "create table stu(nu Integer primary key, name char, score float)");
	ret = sqlite3_exec(db, sql, NULL, NULL, &errmsg);
	if (ret != SQLITE_OK) {
		fprintf(stderr, "create fail : %s\n", errmsg);
		return -1;
	}

	/* 插入數據 */
	int nu = 3;
	char name[20] = "xiaoli";
	float score = 89;

	sprintf(sql, "insert into stu values(%d, '%s', %f)", nu, name, score);
	ret = sqlite3_exec(db, sql, NULL, NULL, &errmsg);
	if (ret != SQLITE_OK) {
		fprintf(stderr, "create fail : %s\n", errmsg);
		return -1;
	}

	sleep(10);

	/* 修改數據 */
	nu = 2;
	strcpy(name, "xiaowang");
	sprintf(sql, "update stu set name='%s' where nu='%d'", name, nu);
	ret = sqlite3_exec(db, sql, NULL, NULL, &errmsg);
	if (ret != SQLITE_OK) {
		fprintf(stderr, "create fail : %s\n", errmsg);
		return -1;
	}

	/* 查詢數據 */
	char test[20];
	sprintf(sql, "select * from stu");
	ret = sqlite3_exec(db, sql, callback, test, &errmsg);
	if (ret != SQLITE_OK) {
		fprintf(stderr, "create fail : %s\n", errmsg);
		return -1;
	}

#endif
	char **result;
	int row;
	int column;
	sprintf(sql, "select * from stu");
	ret = sqlite3_get_table(db, sql, &result, &row, &column, &errmsg);
	if (ret != SQLITE_OK) {
		fprintf(stderr, "select fail : %s\n", errmsg);
		return -1;
	}
	printf("row = %d, column = %d\n", row, column);

	int i;
	int j;
	result += column;
#if 1
	for (i = 0; i < row; i++) {
		for (j = 0; j< column; j++) {
			printf("%s ", *result++);
		}
		printf("\n");
	}
#endif

	sqlite3_close(db);
}

英英詞典代碼：

/*******server.c*********************************************************************************/
#include<stdio.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<string.h>
#include<arpa/inet.h>
#include<unistd.h>
#include<pthread.h>
#include<sqlite3.h>
#include<time.h>
#include<sys/stat.h>
#include<fcntl.h>
int server_start(int listenfd);             //服務器初始化函數
int server_accept(int listenfd);            //服務器連接客戶端函數
void *thread_func(void *connfd);            //線程的處理函數
int server_register(int connfd);            //服務器註冊函數
int server_login(int connfd);               //服務器登陸函數 
int server_search(int connfd,int l);        //服務器搜索單詞函數
int server_history(int connfd,int l);       //服務器歷史紀錄傳給客戶端函數
int server_history_write(char *word);       //服務器歷史記錄寫入文件函數

int main()
{
    int ret;
    int listenfd;
    listenfd = server_start(listenfd);
    if(-1 == ret )
    {
        printf("server_start failed\n");
        return -1;
    }

    while(1)
    {
        //建立連接    
        int connfd;
        connfd = server_accept(listenfd);
        if(-1 == connfd)
        {
            printf("server_accept failed\n");
            return -1;
        }

        //採用多線程的方式
        pthread_t thread;
        ret = pthread_create(&thread,NULL,thread_func,(void *)&connfd);
        if (0 != ret)
        {
            perror("pthread_creat");
            close(connfd);
            continue;
        }
        printf("pthread_creat success! connfd\n");

        //給線程收屍體，用pthread_join會阻塞
        if(0 != pthread_detach(thread))
        {
            perror("pthread_detach");
            close(connfd);
            continue;
        }
    }
    return 0;
}

/********************************************************************/
/*******************服務器初始化**************************************/
int server_start(int listenfd)
{
    /*1.socket*/
    int ret;
    listenfd = socket(AF_INET,SOCK_STREAM,0);
    if(-1 == listenfd)
    {
        perror("server->socket");
        return -1;
    }
    printf("created listenfd = %d success\n",listenfd);

    /*2.bind*/
    struct sockaddr_in addr;
    memset(&addr,0,sizeof(struct sockaddr));
    addr.sin_family = AF_INET;
    addr.sin_port = htons(9999);
    addr.sin_addr.s_addr = htonl(INADDR_ANY);
    ret = bind(listenfd,(const struct sockaddr *)&addr,sizeof(struct sockaddr_in));
    if(-1 == ret)
    {
        perror("server->bind");
        return -1;
    }
    printf("port: %d \n",htons(addr.sin_port));

    /*3.listen*/
    ret = listen(listenfd,0);
    if(-1 == ret)
    {
        perror("server->listen");
        return -1;
    }
    printf("listen success\n");

    return listenfd;
}

/********************************************************************/
/******************服務器連接************************************/
int server_accept(int listenfd)
{
    /*4.accept*/
    socklen_t addrlen;
    struct sockaddr_in cltaddr;
    addrlen = sizeof(socklen_t);
    int connfd;
    connfd = accept(listenfd,(struct sockaddr *)&cltaddr,&addrlen);
    if(-1 == connfd)
    {
        perror("server->accept");
        return -1;
    }
    printf("connfd = %d\n",connfd);
    return connfd;
}

/********************************************************************/
/************線程的處理函數*****************************************/
void *thread_func(void *arg)
{
    int connfd = *(int *)arg;
    int ret;
    int l;
    int chause;
    char buf[256];
    char word[16];
    while(1)
    {
        ret = read(connfd,&chause,sizeof(chause));//接收chause
        //printf("chause = %d\n",chause);
        if(-1 == ret)
        {
            perror("server->read");
            close(connfd);
            pthread_exit(0);
        }

        switch(chause)
        {
            case 1:
                server_register(connfd);
                break;
            case 2:
                l = server_login(connfd);
                break;
            case 3:
                server_search(connfd,l);
                break;
            case 4:
                server_history(connfd,l);
                break;
            case 5:
                printf("this client quit\n");
                close(connfd);
                pthread_exit(0);
            default:
                continue;
        }
    }
}

/********************************************************************/
/********註冊***********************************/
int server_register(int connfd)
{
    char buf[256];
    char buf2[256];
    int ret;
    char name[16];
    char mima[16];
    char sql[256];
    sqlite3 *db;
    char *errmsg;
    int k = 1;//用來保存註冊是否成功的狀態
    memset(sql,0,sizeof(sql));
    memset(buf,0,sizeof(buf));
    memset(buf2,0,sizeof(buf2));

    ret = read(connfd,buf,sizeof(buf));//name
    strncpy(name,buf,16);
    if(-1 == ret)
    {
        perror("server_register->read.name");
        return -1;
    }

    ret = read(connfd,buf2,sizeof(buf2));//mima
    strncpy(mima,buf2,16);
    if(-1 == ret)
    {
        perror("server_register->read.mima");
        return -1;
    }

    /*打開數據庫文件*/
    ret = sqlite3_open("my.db",&db);
    if(SQLITE_OK != ret)
    {
        fprintf(stderr,"open:%s\n",sqlite3_errmsg(db));
        return -1;
    }
#if 0
    /*創建表之前應該判斷下有沒有user這個表，如果有就不創建了*/
    sprintf(sql,"create table user(name char primary key,mima Interger)");
    ret = sqlite3_exec(db,sql,NULL,NULL,&errmsg);
    if(SQLITE_OK != ret)
    {
        fprintf(stderr,"create:%s\n",errmsg);
        return -1;
    }
#endif
    memset(sql,0,sizeof(sql));
     
    /*插入數據*/
    sprintf(sql,"insert into user values('%s','%s')",name,mima);
    ret = sqlite3_exec(db,sql,NULL,NULL,&errmsg);
    if(SQLITE_OK != ret)
    {
        k = 0;
        fprintf(stderr,"insert:%s\n",errmsg);
        ret = write(connfd,&k,sizeof(k));
        if(-1 == ret)
        {
            perror("server_login->write k");
            return -1;
        }
        return -1;
    }
    ret = write(connfd,&k,sizeof(k));
    if(-1 == ret)
    {
        perror("server_login->write k");
        return -1;
    }

    printf("註冊成功\n");
    return 0;
}

/********************************************************************/
/*********登陸********************************/
int server_login(int connfd)
{
    int ret;
    char buf[16];
    char buf2[16];
    char sql[256];
    char sql1[256];
    char name[16];
    char mima[16];
    char *errmsg;
    sqlite3 *db;
    memset(buf,0,sizeof(buf));
    memset(buf2,0,sizeof(buf2));
    memset(sql,0,sizeof(sql));
    memset(sql1,0,sizeof(sql1));
    ret = read(connfd,buf,sizeof(buf));//name
    strncpy(name,buf,16);
    if(-1 == ret)
    {
        perror("server_register->read.name");
        return -1;
    }

    ret = read(connfd,buf2,sizeof(buf2));//mima
    strncpy(mima,buf2,16);
    if(-1 == ret)
    {
        perror("server_register->read.mima");
        return -1;
    }

    /*打開數據庫文件*/
    ret = sqlite3_open("my.db",&db);
    if(SQLITE_OK != ret)
    {
        fprintf(stderr,"open:%s\n",sqlite3_errmsg(db));
        return -1;
    }
    /*查詢數據*/
    char **result;
    int row;
    int column;
    int b = 1;
    sprintf(sql,"select * from user where name='%s' and mima='%s'",name,mima);
    printf("name = %s,mima=%s\n",name,mima);
    ret = sqlite3_get_table(db,sql,&result,&row,&column,&errmsg);
    if(SQLITE_OK != ret)
    {
        fprintf(stderr,"select:%s\n",errmsg);
        return -1;
    }
    if((1 == row))
    {
        printf("login success\n");
        ret = write(connfd,&b,sizeof(b));
        if(-1 == ret)
        {
            perror("server_login->write");
            return -1;
        }
        return 0;
    }
    else
    {
        b = 0;
        ret = write(connfd,&b,sizeof(b));
        if(-1 == ret)
        {
            perror("server_login->write");
            return -1;
        }
        printf("login fail\n");
        return -1;
    }
}

/********************************************************************/
/**********搜索*********************************/
int server_search(int connfd,int l)
{
    int ret;
    char r = '0';
    char buf[1024];
    char b[256];
    char word[64];
    memset(buf,0,sizeof(buf));
    memset(b,0,sizeof(b));
    memset(word,0,sizeof(word));
    if(0 != l)
    {
        printf("please login\n");
        return 0;
    }

    ret = read(connfd,word,sizeof(word));
    if(-1 == ret)
    {
        perror("server_search->read");
        return -1;
    }

    ret = server_history_write(word);///////////////寫入歷史紀錄文檔 
    if(-1 == ret)
    {
        printf("history write fail\n");
    }

    FILE *fp;
    fp = fopen("dict.txt","r");
    while(1)
    {
        int i = 0;
        int k = 1;
        memset(buf,0,sizeof(buf));
        if (NULL == fgets(buf,sizeof(buf),fp))
        {
            break;
        }
        while(word[i])
        {
            if(word[i] != buf[i])
            {
                k = 0;
                break;
            }
            i++;
        }
        if((k == 1) && (buf[i++] ==' '))
        {
            ret = write(connfd,buf,strlen(buf));
            r = '1';//表示找到這個單詞
            if(-1 == ret)
            {
                perror("server_search->write");
                return -1;
            }
            break;
        }
    }
    //r = 0;//表示沒找到這個單詞
    if(r == '0')
    {
        ret = write(connfd,&r,sizeof(r));
        if(-1 == ret)
        {
            perror("server_serach->noword");
            return -1;
        }
    }
    return 0;
}

/********************************************************************/
/***********歷史記錄寫入文件********************************/
int server_history_write(char *word)
{
    FILE *fp;
    size_t ret;
    char buf[64];
    memset(buf,0,sizeof(buf));
    time_t t;
    time(&t);
    struct tm *tp = localtime(&t);
    int i = 0;
    fp = fopen("history.txt","a+");
    if(NULL == fp)
    {
        perror("fopen");
        return -1;
    }
    fprintf(fp,"%2d-%2d  %2d:%2d:%2d :  ",tp->tm_mon +1,tp->tm_mday,tp->tm_hour,tp->tm_min,tp->tm_sec);
    
    while('\0' != word[i])//word  len
    {
        i++; 
    }

    ret = fwrite(word,i,1,fp);
    if(-1 == ret)
    {
        perror("server_history->write time");
        return -1;
    }

    ret = fwrite("\n",1,1,fp);
    if(-1 == ret)
    {
        perror("server_history->write huanhang");
        return -1;
    }
    fclose(fp);
    return 0;
}

/********************************************************************/
/****************歷史紀錄讀出來，傳給服務器 *******************/
int server_history(int connfd,int l)
{
    int fd;
    char buf[128];
    memset(buf,0,sizeof(buf));
    int ret;
    FILE *fp;
    int i = 0;
    if(0 != l)
    {
        return -1;
    }
    fp = fopen("history.txt","r");
    if(NULL == fp)
    {
        perror("fopen");
        return -1;
    }
    while(NULL != fgets(buf,sizeof(buf),fp))// 獲得行號
    {
        i++;
    }
    fclose(fp);

    ret = write(connfd,&i,sizeof(i));//發送行號
    if(-1 == ret)
    {
        perror("server_history->line");
        return -1;
    }

    fp = fopen("history.txt","r");
    while(NULL != fgets(buf,sizeof(buf),fp))// 發送具體內容
    {
        ret = write(connfd,buf,sizeof(buf));
        if(-1 == ret)
        {
            perror("server_history->write");
            return -1;
        }
    }
    fclose(fp);
    return 0;
}



/********client.c******************************************************************************/
#include<stdio.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<string.h>
#include<arpa/inet.h>
#include<unistd.h>
int client_start(int sockfd);             //客戶端初始化函數
void client_meau(void);                   //客戶端菜單函數
int client_register(int sockfd);          //客戶端註冊函數
int client_login(int sockfd);             //客戶端登陸函數
int client_search(int sockfd,int l);      //客戶端搜索單詞函數
int client_history(int sockfd,int l);     //客戶端查詢歷史記錄函數
int client_name(int sockfd);              //客戶端登陸和註冊輸入名字函數
int client_mima(int sockfd);              //客戶端登陸和註冊輸入密碼函數

int main()
{
    int ret;
    int sockfd;
    int chause;
    int l = 2;
    char buf[256];
    sockfd = client_start(sockfd);
    if(-1 == sockfd)
    {
        printf("client_start failed\n");
        return -1;
    }

    while(1)
    {
        client_meau();
        scanf("%d",&chause);
        memset(buf,0,sizeof(buf));
        ret = write(sockfd,&chause,sizeof(chause));//傳chause給服務器
        if(-1 == ret)
        {
            perror("client->write");
            continue;
        }

        switch(chause)
        {
            case 1:
                client_register(sockfd);
                break;
            case 2:
                l = client_login(sockfd);//用l保存登陸的狀態
                break;
            case 3:
                client_search(sockfd,l);
                break;
            case 4:
                client_history(sockfd,l);
                break;
            case 5:
                return 0;
            default:
                printf("請選擇正確的選項\n");
                continue;
        }
    }
    close(sockfd);
    return 0;
}

/*************************************************************/
/***********客戶端********************************************/
int client_start(int sockfd)
{
    int ret;
    /*1.socket*/
    sockfd = socket(AF_INET,SOCK_STREAM,0);
    if(-1 == sockfd)
    {
        perror("server->socket");
        return -1;
    }
    printf("sockfd = %d\n",sockfd);

    /*2.connect*/
    struct sockaddr_in addr;
    memset(&addr,0,sizeof(struct sockaddr));
    addr.sin_family = AF_INET;
    addr.sin_port = htons(9999);
    addr.sin_addr.s_addr = htonl(INADDR_ANY);
    ret = connect(sockfd,(const struct sockaddr *)&addr,sizeof(struct sockaddr_in));
    if(-1 == ret)
    {
        perror("server->bind");
        return -1;
    }
    printf("connect success\n");
    return sockfd;
}

/*************************************************************/
/**********主菜單******************************************/
void client_meau(void)
{
    printf("**********請您選擇要進行的操作****************\n");
    printf("----------------------------------------------\n");
    printf("|           -.-*英英詞典*-.-                 |\n");
    printf("|                * __ *                      |\n");
    printf("|                                            |\n");
    printf("|           1.用戶註冊                       |\n");
    printf("|           2.用戶登陸                       |\n");
    printf("|           3.單詞在線翻譯                   |\n");
    printf("|           4.歷史記錄查詢                   |\n");
    printf("|           5.退出                           |\n");
    printf("|                                            |\n");
    printf("----------------------------------------------\n");
    printf("\n");
    printf("input:");
}

/*************************************************************/
/***********註冊*****************************************/
int client_register(int sockfd)
{
    int ret;
    int k = 0;// 保存註冊的狀態
    ret = client_name(sockfd);
    if(-1 == ret)
    {
        printf("name failed\n");
        return -1;
    }

    ret = client_mima(sockfd);
    if(-1 == ret)
    {
        printf("mima failed\n");
        return -1;
    }

    ret = read(sockfd,&k,sizeof(k));
    if(-1 == ret)
    {
        printf("client_register->read k\n");
        return -1;
    }
    if(k == 1)
    {
        printf("註冊成功\n");
    }
    else
    {
        printf("註冊失敗\n");
    }
    return 0;
}

int client_name(int sockfd)//name
{
    char name;
    int ret;
    char buf[16];
    memset(buf,0,sizeof(buf));
    fprintf(stdout,"請輸入帳號:\n");
    scanf("%s",buf);
    //buf[strlen(buf)-1] = '\0';
    if(0 == strlen(buf))
    {
        printf("name is null\n");
        return -1;
    }
    ret = write(sockfd,buf,sizeof(buf));
    if(-1 == ret)
    {
        perror("client_register->write.name");
        printf("failed\n");
        return -1;
    }
    return 0;
}

int client_mima(int sockfd)//mima
{
    char mima;
    int ret;
    char buf[16];
    fprintf(stdout,"請輸入密碼\n");
    scanf("%s",buf);
    //buf[strlen(buf)-1] = '\0';
    if(0 == strlen(buf))
    {
        printf("mima is null\n");
        return -1;
    }
    ret = write(sockfd,buf,sizeof(buf));
    if(-1 == ret)
    {
        perror("client_register->write.mima");
        printf("failed\n");
        return -1;
    }
    return 0;
}




/*************************************************************/
/************登陸****************************************/
int client_login(int sockfd)
{
    int ret;
    char buf[16];
    int b = 0;
    memset(buf,0,sizeof(buf));
    client_name(sockfd);
    if(-1 == ret)
    {
        printf("name failed\n");
        return -1;
    }
    client_mima(sockfd);
    if(-1 == ret)
    {
        printf("mima failed\n");
        return -1;
    }

    ret = read(sockfd,&b,sizeof(b));
    if(-1 == ret)
    {
        perror("client_register->write.mima");
        printf("failed\n");
        return -1;
    }

    if(1 == b)
    {
        printf("login success\n");
        return 0;
    }
    else
    {
        printf("login fail\n");
        return -1;
    }
}

/*************************************************************/
/***********搜索************************************/
int client_search(int sockfd,int l)
{
    char word[64];
    int ret;
    char r = '1';
    char buf[1024];
    memset(word,0,sizeof(word));
    memset(buf,0,sizeof(buf));
    if(0 != l)
    {
        printf("please login\n");
        return -1;
    }

    printf("請輸入要搜索的單詞:\n");
    scanf("%s",word);
    ret = write(sockfd,word,sizeof(word));
    if(-1 == ret)
    {
        perror("client_search->write");
        return -1;
    }

    ret = read(sockfd,buf,sizeof(buf));
    if(-1 == ret)
    {
        perror("client_search->read");
        return -1;
    }

    if('0' == buf[0])
    {
        printf("no the word\n");
    }
    else
    {
        printf("查詢內容:%s\n",buf);
    }
    return 0;
}

/*************************************************************/
/*************歷史查詢*************************************/
int client_history(int sockfd,int l)
{
    char buf[128];
    int ret;
    int i = 0;

    if(0 != l)
    {
        printf("please login\n");
        return -1;
    }

    ret = read(sockfd,&i,sizeof(i));
    if(-1 == ret)
    {
        perror("client_history->line");
        return -1;
    }

    printf("一共有%3d個歷史數據\n",i);
    while(i--)
    {
        memset(buf,0,sizeof(buf));
        ret = read(sockfd,buf,sizeof(buf));
        if(-1 == ret)
        {
            perror("client_history->read");
            return -1;
        }
        printf("%s",buf);
    }
    printf("\n");
    return 0;
}




/**Makefile******************************************************************/
all:
	gcc server.c -o server -lpthread -lsqlite3
	gcc client.c -o client -lsqlite3
.PHONY:clean
clean:
	rm server client