FIX: Darwin not based on /dev/vsock file

Author: Fred78290

fd_darwin.go

@@ -2,22 +2,21 @@ package vsock
 
 import (
 	"fmt"
-	"os"
 
 	"golang.org/x/sys/unix"
 )
 
 // contextID retrieves the local context ID for this system.
 func contextID() (uint32, error) {
-	f, err := os.Open(devVsock)
-	if err != nil {
-		return 0, err
-	}
-	defer f.Close()
+	if fd, err := unix.Socket(unix.AF_VSOCK, unix.SOCK_STREAM, 0); err != nil {
+		return 2, nil
+	} else {
+		defer unix.Close(fd)
 
-	cid, err := unix.IoctlGetInt(int(f.Fd()), unix.IOCTL_VM_SOCKETS_GET_LOCAL_CID)
+		cid, err := unix.IoctlGetInt(fd, unix.IOCTL_VM_SOCKETS_GET_LOCAL_CID)
 
-	return uint32(cid), err
+		return uint32(cid), err
+	}
 }
 
 // isErrno determines if an error a matches UNIX error number.

vsock_darwin_test.go

@@ -86,21 +86,6 @@ func Test_opError(t *testing.T) {
 				Err: errClosed,
 			},
 		},
-		{
-			name: "special PathError /dev/vsock",
-			err: &os.PathError{
-				Op:   "open",
-				Path: devVsock,
-				Err:  unix.ENOENT,
-			},
-			want: &net.OpError{
-				Err: &os.PathError{
-					Op:   "open",
-					Path: devVsock,
-					Err:  unix.ENOENT,
-				},
-			},
-		},
 		{
 			name:   "op close",
 			op:     opClose,