ucontext32
struct ucontext32;
extern void xregs_clrptr32(struct _klwp *, struct ucontext32 *);
extern int xregs_hasptr32(struct _klwp *, struct ucontext32 *);
extern caddr32_t xregs_getptr32(struct _klwp *, struct ucontext32 *);
extern void xregs_setptr32(struct _klwp *, struct ucontext32 *, caddr32_t);