Among other features, pervasive computing aims at offering access to users' data, anytime, anywhere, in a transparent manner. However, realizing such a vision necessitates several improvements in the way servers and users terminals interact. In particular, users terminals should not tightly rely on an information server, which can be temporarily unavailable in a mobile situation. They should rather exploit all the information servers available in a given context through loose coupling with both fixed servers and groups of mobile terminals, in a serverless manner. This paper presents the AdHocFS serverless file system that realizes transparent adaptive file access according to the users' specific situations (e.g. device in use, network connectivity, etc).