os/file_unix: add runtime function net.NewFile stub

Signed-off-by: leongross <leon.gross@9elements.com>

src/os/file_unix.go

@@ -12,6 +12,7 @@ package os
 import (
 	"io"
 	"syscall"
+	_ "unsafe"
 )
 
 const DevNull = "/dev/null"
@@ -223,3 +224,17 @@ func newUnixDirent(parent, name string, typ FileMode) (DirEntry, error) {
 	ude.info = info
 	return ude, nil
 }
+
+// Since internal/poll is not available, we need to stub this out.
+// Big go requires the option to add the fd to the polling system.
+//
+//go:linkname net_newUnixFile net.newUnixFile
+func net_newUnixFile(fd int, name string) *File {
+	if fd < 0 {
+		panic("invalid FD")
+	}
+
+	// see src/os/file_unix.go:162 newFile for the original implementation.
+	// return newFile(fd, name, kindSock, true)
+	return NewFile(uintptr(fd), name)
+}