chgat
extern int chgat(int, attr_t, short, const void *);
#define mvchgat(y,x,n,a,co,p) (move(y,x)?ERR:chgat(n,a,co,p))
(chgat)(int n, attr_t at, short co, const void *opts)
extern int chgat(int, attr_t, short, const void *);
(move(y, x) ? (n, a, co, p, ERR) : chgat(n, a, co, p))