+bool util_filexists(const char *file) {
+ FILE *fp = fopen(file, "rb");
+ if (!fp) return false;
+
+ /* it exists */
+ fclose(fp);
+ return true;
+}
+
+void _util_vec_grow(void **a, size_t i, size_t s) {
+ size_t m = *a ? 2*_vec_beg(*a)+i : i+1;
+ void *p = mem_r((*a ? _vec_raw(*a) : NULL), s * m + sizeof(size_t)*2);
+ if (!*a)
+ ((size_t*)p)[1] = 0;
+ *a = (void*)((size_t*)p + 2);
+ _vec_beg(*a) = m;
+}