xcalloc
#define xcalloc(n, s) Calloc(n, s)
xcalloc(size_t size)
xcalloc(size_t number, size_t size)
xcalloc(size_t nmemb, size_t size)
xcalloc(size_t n, size_t s, const char *fmt, ...)
xcalloc(size_t n, size_t s)