如果在 ATL 组件程序中调用了 CRT 的运行时刻库函数，比如开平方 sqrt() ，那么编译的时候可能会报错“error LNK2001: unresolved external symbol _main”。怎么办？下面方法中的任何一个都可以纠正这个错误：-If the ATL component called the CRT-program run-time library functions, such as the square root sqrt (), then the compiler will complain when possible " error LNK2001: unresolved external symbol _main" . How to do? Any one of the following methods can rectify this error: