Thank you very much for your patience and help. I got it and will try it
later. :)
在 2017年8月7日星期一 UTC+8下午3:52:43，Konstantin Khomoutov写道：
>
> On Sun, Aug 06, 2017 at 07:08:03PM -0700, jianzh...@gmail.com
> <javascript:> wrote:
>
> > Thanks your reply, I also used this way, but it still not work. code as
> the
> > following.
> >
> > gonameunits := []string{"gpu0", "gpu1", "gpu2", "gpu3"}
> > nameunits := make([]*C.char, len(gonameunits))
> > for i, _ := range gonameunits {
> > nameunits[i] = C.CString(gonameunits[i])
> > defer C.free(unsafe.Pointer(nameunits[i]))
> > }
> > fmt.Println("nameunits:", nameunits)
>
> This looks correct...
>
> > golevelmatrix := [][]int{{1}, {3, 3}, {3, 3, 2}}
> > levelmatrix := make([][]C.int, len(golevelmatrix))
> > for i, _ := range golevelmatrix {
> > levelmatrix[i] = make([]C.int, len(golevelmatrix[i]))
> > for j, _ := range golevelmatrix[i] {
> > levelmatrix[i][j] = C.int(golevelmatrix[i][j])
> > }
> > }
>
> ...but this is not: remember that in Go, the type []T denotes *a slice* of
> elements of type T. A slice is a dynamic construct which is a view into
> underlying array, and as such it itself consists of a pointer into that
> array's contents, the current length of the slice and the capacity of
> it.
>
> > fmt.Println("levelmatrix:", levelmatrix)
> >
> > C.test_settopologyresource(mod, C.CString("node1"), C.int(2),
> (**C.char
> > )(unsafe.Pointer(&nameunits[0])),
> (**C.int)(unsafe.Pointer(&levelmatrix[0][0
> > ])))
>
> That thing about slices means that passing a pointer to a single slice
> element to C is OK; passing a pointer to an Nth element of a slice to C
> and expecting it to access it and the elements following it up to the
> slice's length is also OK but interpreting a slice of slices (which
> [][]*C.int really is) is wrong: it's not represented by a contiguous
> array: it's a slice of N independent slices -- each backed by its
> independent array.
>
> So what you really want is something like:
>
> 1. Know the dimensions of your matrix (let's denote them by N and M).
> 2. Allocate a slice of the length N*M.
> 3. Fill it up with the values from your source slice of slices.
> 4. Pass the pointer to the array to C.
>
> Like this (untested, may not even compile):
>
> n := len(golevelmatrix)
> m := 0
> for _, row := range golevelmatrix {
> if len(row) > m {
> m = len(row)
> }
> }
>
> a := make([]int, n*m)
> i := 0
> for _, row := range golevelmatrix {
> for j, v := range row {
> a[i*n+j] = v
> }
> i++
> }
>
> C.my_func(&a[0])
>
>
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