* in any IO with the server. Unlink <code>InputStream</code> value less than
     * the one provided will not be returned if it exceeds the end of the file
     * (if this is a problem let us know).
     */
    @Override
    public long skip(final long n) throws IOException {
        if (n > 0) {
            this.fp += n;
            return n;
        }
        return 0;
    }

In this case, it is an `async` function.

---

You could also define it as a normal function instead of `async def`:

{* ../../docs_src/first_steps/tutorial003.py hl[7] *}

/// note

If you don't know the difference, check the [Async: *"In a hurry?"*](../async.md#in-a-hurry){.internal-link target=_blank}.

///

### Step 5: return the content { #step-5-return-the-content }

    @Override
    public void init(final FilterConfig filterConfig) throws ServletException {
        String name;

        final Properties p = new Properties();
        /*
         * Set jcifs properties we know we want; soTimeout and cachePolicy to 30min.
         */
        p.setProperty("jcifs.smb.client.soTimeout", "1800000");
        p.setProperty("jcifs.netbios.cachePolicy", "1200");
        /*

I used to say I didn't like history that much... and look at me now giving "tech history" lessons. 😅

					entry = strings.TrimSuffix(entry, globalDirSuffixWithSlash) + slashSeparator
					dirObjects[entry] = struct{}{}
					entries[i] = entry
					continue
				}
				// Trim slash, since we don't know if this is folder or object.
				entries[i] = entries[i][:len(entry)-1]
				continue
			}
			// Do not retain the file.
			entries[i] = ""

			if contextCanceled(ctx) {
				return ctx.Err()
			}

    // that have the same key. Then a second pass will remove all but the first of the slots that
    // have this Entry. The value in the map becomes false when this first entry has been copied, so
    // we know not to copy the remaining ones.
    IdentityHashMap<Entry<K, V>, Boolean> duplicates = null;
    int dupCount = 0;
    for (int entryIndex = n - 1; entryIndex >= 0; entryIndex--) {

              // it's unnecessary to waste cycles looking at them. This check is built on the
              // observation that the header entries we care about are in adjacent pairs, and we
              // always know the first index of the pair.
              if (STATIC_HEADER_TABLE[headerNameIndex - 1].value == value) {
                headerIndex = headerNameIndex
              } else if (STATIC_HEADER_TABLE[headerNameIndex].value == value) {

By returning the result of calling `generate_html_response()`, you are already returning a `Response` that will override the default **FastAPI** behavior.

But as you passed the `HTMLResponse` in the `response_class` too, **FastAPI** will know how to document it in OpenAPI and the interactive docs as HTML with `text/html`:

<img src="/img/tutorial/custom-response/image01.png">

## Available responses { #available-responses }

                    } else {
                        encodedBuf.append(converted);
                    }
                } catch (final UnsupportedEncodingException e) {
                    // NOP
                }
            }
        }

        final String id = encodedBuf.toString();
        return MessageDigestUtil.digest(ComponentUtil.getFessConfig().getIndexIdDigestAlgorithm(), id);
    }

That way, you can create a token with an expiration of, let's say, 1 week. And then when the user comes back the next day with the token, you know that user is still logged in to your system.