> xauth add unix:0 . b90b0fd1cf6a0e7a2c74c00000000004
  exits with 0
> xauth add 127.0.0.1:1 . b90b0fd1cf6a0e7a2c74c00000000005
  exits with 0
> xauth add :2 . b90b0fd1cf6a0e7a2c74c00000000006
  exits with 0
> xauth add :3.5 . b90b0fd1cf6a0e7a2c74c00000000007
  exits with 0
> xauth add :4 . b90b0fd1cf6a0e7a2c74c00000000004
  exits with 0
7
list
b90b0fd1cf6a0e7a2c74c00000000004
0
list
b90b0fd1cf6a0e7a2c74c00000000005
0
list
b90b0fd1cf6a0e7a2c74c00000000006
0
list
b90b0fd1cf6a0e7a2c74c00000000007
0
list
b90b0fd1cf6a0e7a2c74c00000000004
0