循环 mysql_real_connect 或什么 [英] looping mysql_real_connect or what

问题描述

考虑以下 c 代码:

int main (int argc, char *argv[]) {
  MYSQL *sql_handle;

  fprintf(stdout,"initializing handle..\n");
  sql_handle = mysql_init(sql_handle);

  fprintf(stdout,"connecting to database..\n");
  mysql_real_connect(sql_handle,NULL,NULL,
                      NULL,"test",0,NULL,0);

  fprintf(stdout,"connection established\n");
  mysql_close(sql_handle);
}

这会产生以下输出

...
initializing handle..
connecting to database..
initializing handle..
connecting to database..
initializing handle..
connecting to database..
initializing handle..
connecting to database..
connection established
Error: Can't create UNIX socket (24)

real_connect 函数似乎有问题.守护进程肯定正在运行.很久以前我习惯了 c 所以这可能是一个愚蠢的问题.

the real_connect function seems to have problems. the daemon is running for sure. it's long time ago since i was used to c so this might be a stupid question.

[更新]这是完整的代码

  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 
  4 #if defined __WIN32__ || _MSC_VER
  5    #include "my_global.h"
  6    #include "mysql.h"
  7 #else
  8    #include <mysql.h>
  9 #endif
 10 
 11 /* prototypes */
 12 void connect(void);
 13 
 14 /* sql handle */
 15 MYSQL *sql_handle;
 16 
 17 int main (int argc, char *argv[]) {
 18   fprintf(stdout,"main..\n");
 19   connect();
 20   return EXIT_SUCCESS;
 21   
 22 } 
 23 void connect(void){
 24   fprintf(stdout,"initializing database handle..\n");
 25   sql_handle = mysql_init(NULL);
 26   
 27   fprintf(stdout,"connecting to database..\n");
 28   mysql_real_connect(sql_handle,NULL,NULL,NULL,NULL,0,NULL,0);
 29   
 30   fprintf(stdout,"closing connection..\n");
 31   mysql_close(sql_handle);
 32 } 

此代码产生该输出:

...
connecting to database..
initializing database handle..
connecting to database..
initializing database handle..
connecting to database..
closing connection..
[1]    12914 segmentation fault (core dumped)  ./db

将连接函数的主体复制到 main 中并删除连接函数可解决此问题.但这不是解决方案.

copying the body of the connect-function into main and removing the connect-functions resolves the issue. but this is not a solution.

推荐答案

重命名方法

void connect(void)

到

void connect_to_database(void)

为我解决了这个问题

这篇关于循环 mysql_real_connect 或什么的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！