musl-tcc/src/dirent/__dirent.h

struct __dirstream
{
	off_t tell;
	int fd;
	int buf_pos;
	int buf_end;
	volatile int lock[1];
	/* Any changes to this struct must preserve the property:
	 * offsetof(struct __dirent, buf) % sizeof(off_t) == 0 */
	char buf[2048];
};