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