查询mysql的简单代码【c】

  好久没有学习C/c++了，也好久没有用了，前几天有时间的时候，就写了一个，目前正在坚持看《UNIX环境高级编程》，希望早日能够看透。

#include
#include
#include
#include
MYSQL mysql;  
int main(int argc,char *argv[])
{
 char host[32]="localhost";
 char user[32]="root";
 char passwd[32]="";
 char dbname[32]=""; 
       
        char ip[65]; 
       
        if (argc != 2)
        {
          printf("usage: %s ip\n",argv[0]);
          return -1;
        }
       
        sprintf(ip,argv[1]);
          
 if( mysql_init(&mysql) == NULL )
 {
  printf("inital mysql handle error\n");
  return 1;
 }
 if (mysql_real_connect(&mysql,host,user,passwd,dbname,0,NULL,0) == NULL)
 {
  printf("Failed to connect to database: Error: %s\n",mysql_error(&mysql));
  return 1;
 }
 
        MYSQL_ROW m_row;
        MYSQL_RES *m_res;
        char sql[1024];
        int res=1;
        int t,r;
 
        sprintf(sql,"select password from t_passwd_info  where host='%s' and username='root'",ip);
        if(mysql_query(&mysql,sql) != 0)
        {
              printf("select ps_info Error: %s\n",mysql_error(&mysql));
              return res;
        }
      
        m_res = mysql_use_result(&mysql);
        m_row=mysql_fetch_row(m_res);
        printf("%s\n",m_row[0]);
  
 db_close();
}

int db_close()
{
        mysql_close(&mysql);
         return 0;
}

简单的一个c查询