如何在golang的额外软件包中使用主软件包记录器？

I want to make global logger.

Can I make global logger? (To access every pacakges)

Packages can have global variables:

package somepackage

import "log"

var (
  Log *log.Logger = log.New(os.Stderr, "", log.LstdFlags)
)

Notice that I capitalized Log. This means it is exported (think public in other languages).

In general though, using globals is discouraged. I would recommend thinking of a different pattern.