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我有C++代码来连接并用mysql:CPP-mysql的未定义的引用“的功能”错误
#include <iostream>
#include <mysql/mysql.h>
using namespace std;
MYSQL *connection, mysql;
MYSQL_RES *result;
MYSQL_ROW row;
int query_state;
int main() {
mysql_init(&mysql);
connection = mysql_real_connect(&mysql,"localhost","root","pass","cpp_data",0,0,0);
if (connection == NULL) {
cout << mysql_error(&mysql) << endl;
return 1;
}
return 0;
}
当我编译,我得到test.cpp:(.text+0x11): undefined reference to 'mysql_init'
和mysql_real_connect
和mysql_error
同样的错误。
我已经试过gcc -o test -L/usr/lib/mysql -lmysqlclient test.cpp
,但这给我以下错误:
test.cpp:(.text+0x7a): undefined reference to `std::cout'
test.cpp:(.text+0x7f): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x87): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::endl<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&)' etc.
我检查mysql.h
和mysql_real_connect
的定义是:
MYSQL * STDCALL mysql_real_connect(MYSQL *mysql, const char *host,
const char *user,
const char *passwd,
const char *db,
unsigned int port,
const char *unix_socket,
unsigned long clientflag);
我没有问题,当我做不使用这些mysql函数。是否有另一个选择来解决这个问题?
so g ++ -o test -L/usr/lib/mysql -lmysqlclient test.cpp实际上是解决这个问题的方法吗? – 2012-01-15 13:02:53
对于未定义的符号,是的。 (尽管你应该在'test.cpp'后面加上'-lmysqlclient'作为该行的结尾。) – Mat 2012-01-15 13:03:45