Array(s) of this structure are used to allow for extensions.
struct wfdcfg_keyval { const char * key ; long i ; void * p ; };
Several Wfdcfg library functions take this structure as an optional argument; certain drivers pass data to the Wfdcfg library using this interface.
The i and p members of this structure depend on the key (when part of an array, an element with key==NULL marks the end of that array). Unused i and/or p fields should be set to 0 or NULL.