xdot man page does not document some functions
lib/xdot/xdot.3 lists the following API:
xdot* parseXDotF (char*, drawfunc_t opfns[], int sz);
xdot* parseXDot (char*);
char* sprintXDot (xdot*);
void fprintXDot (FILE*, xdot*);
void freeXDot (xdot*);
xdot_grad_type colorType (char*);
xdot_color* parseXDotColor (char*);
void freeXDotColor (xdot_color*);
However lib/xdot/xdot.h gives the API as:
XDOT_API xdot* parseXDotF (char*, drawfunc_t opfns[], int sz);
XDOT_API xdot* parseXDotFOn (char*, drawfunc_t opfns[], int sz, xdot*);
XDOT_API xdot* parseXDot (char*);
XDOT_API char* sprintXDot (xdot*);
XDOT_API void fprintXDot (FILE*, xdot*);
XDOT_API void jsonXDot (FILE*, xdot*);
XDOT_API void freeXDot (xdot*);
XDOT_API int statXDot (xdot*, xdot_stats*);
XDOT_API xdot_grad_type colorTypeXDot (char*);
XDOT_API char* parseXDotColor (char* cp, xdot_color* clr);
XDOT_API void freeXDotColor (xdot_color*);
Note there are both missing functions and functions with the wrong prototype.