There is no restriction on the appearance of non-printing characters, apart from the binary zero that terminates a pattern, but when a pattern is being prepared by text editing, it is usually easier to use one of the following escape sequences than the binary character it represents:
Lors de la préparation du masque, il est souvent plus pratique d'utiliser les séquences d'échappement suivantes, plutôt que le caractère binaire qu 'elle représente: