如何通过golang中的CGO将Go字符串复制到C char *？

I want to copy a Go string into a char * via CGO.

Am I allowed to do this something like this?

func copy_string(cstr *C.char) {

    str := "foo"
    C.GoString(cstr) = str

}

According to the cgo documentation you need to use the C.CString function to convert a Go string to a C string:

cstr = C.CString(str)

Be aware that C.CString function allocates the memory for you, but won't release it, so it is your responsability to freed the memory with a call like:

C.free(unsafe.Pointer(cstr))