A VFS server must register with z/OS UNIX by calling the v_reg() service.

v_reg() checks that the VFS server has appropriate privileges (is a superuser), and sets up support for the VFS callable services API.

The input to v_reg() is contained in the NREG structure and includes the name by which the VFS server is to be known.

A DFS-style file exporter also includes the name of an exit program that the LFS is to call before and after every vnode operation for files that are being exported.

Refer to Interface structures for C language servers and clients for a description of the information that is passed during registration.