checkNotClosed();

        // Simple KDF implementation (should be replaced with proper KDF like HKDF)
        // This is a placeholder - real implementation should use proper KDF
        byte[] derived = new byte[length];

        // Combine inputs
        byte[] labelBytes = label.getBytes(java.nio.charset.StandardCharsets.UTF_8);

   *
   * <p>NOTE: an IPv6 address coerced to an IPv4 address can only be used for such purposes as
   * rudimentary identification or indexing into a collection of real {@link InetAddress}es. They
   * cannot be used as real addresses for the purposes of network communication.
   *
   * @param ip {@link InetAddress} to convert
   * @return {@code int}, "coerced" if ip is not an IPv4 address
   * @since 7.0

<p align="center">
  <a href="https://fastapi.tiangolo.com"><img src="https://fastapi.tiangolo.com/img/logo-margin/logo-teal.png" alt="FastAPI"></a>
</p>
<p align="center">
    FastAPI 框架，高效能，易於學習，快速開發，適用於生產環境
</p>
<p align="center">
<a href="https://github.com/fastapi/fastapi/actions?query=workflow%3ATest+event%3Apush+branch%3Amaster" target="_blank">

# FastAPI

<style>
.md-content .md-typeset h1 { display: none; }
</style>

<p align="center">
  <a href="https://fastapi.tiangolo.com"><img src="https://fastapi.tiangolo.com/img/logo-margin/logo-teal.png" alt="FastAPI"></a>
</p>
<p align="center">
    Framework FastAPI, haute performance, facile à apprendre, rapide à coder, prêt pour la production
</p>
<p align="center">

The built-in function <code>complex</code> constructs a complex
value from a floating-point real and imaginary part, while
<code>real</code> and <code>imag</code>
extract the real and imaginary parts of a complex value.
</p>

<pre class="grammar">
complex(realPart, imaginaryPart floatT) complexT
real(complexT) floatT
imag(complexT) floatT
</pre>

<p>

directives that cmd/link is not sophisticated enough to derive from _all.o
on its own. Similarly, the _all.o uses dynamic references to real
system object code because cmd/link is not sophisticated enough to process
the real code.

The main benefits of this system are that cmd/link remains relatively simple
(it does not need to implement a complete ELF and Mach-O linker) and

	err := os.WriteFile(dir2, []byte("hello"), 0o777)
	if err != nil {
		t.Fatal(err)
	}

	if isDirEmpty(dir2, true) {
		t.Error("expected false for a file, got true")
	}

	// Should give true for a real empty directory.
	dir3 := slashpath.Join(tmp, "empty")
	err = os.Mkdir(dir3, 0o777)
	if err != nil {
		t.Fatal(err)
	}

	if !isDirEmpty(dir3, true) {
		t.Error("expected true for empty dir, got false")

are predefined and refer to registers.
The exact set depends on the architecture.
</p>

<p>
There are four predeclared symbols that refer to pseudo-registers.
These are not real registers, but rather virtual registers maintained by
the toolchain, such as a frame pointer.
The set of pseudo-registers is the same for all architectures:
</p>

<ul>

<li>

Te mostraré algunos ejemplos concretos en los próximos capítulos.

---

Luego, los siguientes conceptos a considerar son todos acerca del programa que ejecuta tu API real (por ejemplo, Uvicorn).

## Programa y Proceso

Hablaremos mucho sobre el "**proceso**" en ejecución, así que es útil tener claridad sobre lo que significa y cuál es la diferencia con la palabra "**programa**".

<p align="center">
  <a href="https://fastapi.tiangolo.com"><img src="https://fastapi.tiangolo.com/img/logo-margin/logo-teal.png" alt="FastAPI"></a>
</p>
<p align="center">
    FastAPI framework, high performance, easy to learn, fast to code, ready for production
</p>
<p align="center">
<a href="https://github.com/fastapi/fastapi/actions?query=workflow%3ATest+event%3Apush+branch%3Amaster" target="_blank">