ref: 5d13a50ba5f8139cdd625c9eb0aa3d771c9d146f dir: /util.h/
int isnum(char *s, unsigned int n); int strtodir(char *s); char* dirtostr(int dir); Point parseput(char *x, char *y); int dprint(char *fmt, ...); void* emalloc(unsigned long n);