.writeUtf8("--")
        .writeUtf8(boundary)
        .readByteString()

    /**
     * This delimiter typically precedes all subsequent parts. It may also precede the first part
     * if the body contains a preamble.
     */
    private val crlfDashDashBoundary =
      Buffer()
        .writeUtf8("\r\n--")
        .writeUtf8(boundary)
        .readByteString()

    private var partCount = 0
    private var closed = false

as C.stdout, or functions such as C.putchar.

If the import of "C" is immediately preceded by a comment, that
comment, called the preamble, is used as a header when compiling
the C parts of the package. For example:

	// #include <stdio.h>
	// #include <errno.h>
	import "C"

The preamble may contain any C code, including function and variable
declarations and definitions. These may then be referred to from Go

    /**
     * Default constructor.
     */
    protected NtlmMessage() {
        // Protected constructor for abstract class
    }

    /**
     * The NTLMSSP "preamble".
     */
    protected static final byte[] NTLMSSP_SIGNATURE =
            { (byte) 'N', (byte) 'T', (byte) 'L', (byte) 'M', (byte) 'S', (byte) 'S', (byte) 'P', (byte) 0 };

    /**
     * NTLM version
     */

      parts.nextPart()
    }.also { expected ->
      assertThat(expected).hasMessage("expected at least 1 part")
    }
  }

  @Test fun `skip preamble`() {
    val multipart =
      """
      |this is the preamble! it is invisible to application code
      |
      |--simple boundary
      |
      |abcd
      |--simple boundary--
      """.trimMargin()
        .replace("\n", "\r\n")

    /**
     * Default constructor.
     */
    protected NtlmMessage() {
        // Protected constructor for abstract class
    }

    /**
     * The NTLMSSP "preamble".
     */
    protected static final byte[] NTLMSSP_SIGNATURE =
            { (byte) 'N', (byte) 'T', (byte) 'L', (byte) 'M', (byte) 'S', (byte) 'S', (byte) 'P', (byte) 0 };

  <mime-type type="application/x-axcrypt">
    <_comment>AxCrypt</_comment>
    <glob pattern="*.axx" />
    <magic priority="60">
      <!-- AxCrypt block header, skip length field, then Header of type Preamble -->
      <match value="0xc0b9072e4f93f146a015792ca1d9e821" type="string" offset="0">
         <match value="2" type="big32" offset="17" />
      </match>
    </magic>
  </mime-type>

 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

                            Preamble

  The GNU Affero General Public License is a free, copyleft license for
software and other kinds of works, specifically designed to ensure
cooperation with the community in the case of network server software.