rem: static void writefd(int fd,char *buf,int len)
add: static void writefd(int fd,char *buf,size_t len)
context: static void writefd(int fd,char *buf,int len){	stats.total_written += len;	err_list_push();	if (!io_buffer || fd != multiplex_out_fd) {		writefd_unbuffered(fd, buf, len);		return;	}	while (len) {		int n = MIN(len, IO_BUFFER_SIZE-io_buffer_count);		if (n > 0) {			memcpy(io_buffer+io_buffer_count, buf, n);			buf += n;			len -= n;			io_buffer_count += n;		}				if (io_buffer_count == IO_BUFFER_SIZE) io_flush();	}}