warning: implicit declaration of function ‘XXX’; did you mean ‘YYY’? [-Wimplicit-function-declarati

1. 问题：

warning: implicit declaration of function ‘XXX’; did you mean ‘YYY’? [-Wimplicit-function-declaration]

2. 原因：

“XXX”这个函数所在头文件没有添加。

3. 解决：

找到函数“XXX”所在头文件添加到工程中。

4. 举例：

 warning: implicit declaration of function ‘usleep’; did you mean ‘fseek’? [-Wimplicit-function-declaration]

只要把  #include 添加到头文件处，警告就会消失。

5. 参考：

https://blog.csdn.net/fireroll/article/details/8651593

https://stackoverflow.com/questions/10053788/implicit-declaration-of-function-usleep