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eml886 B

EML: RFC 2231 Continuation Filename With size and creation-date

The conformant answer to non-ASCII filenames: a filename split into three numbered RFC 2231 segments with a charset and a language tag, plus size and creation-date parameters. Parsers commonly handle filename*= but not the numbered continuation form.

Email parsingEncoding detectionInternationalization
Preview, first 27 lineseml
From: Meridian Ops <ops@meridiansupply.example>
To: Sam Rivera <sam@meridiansupply.example>
Subject: RFC 2231 continuation filename
Date: Fri, 13 Feb 2026 11:15:00 -0800
Message-ID: <p7-disp-2231@brightside.example>
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="=_p7_disp_2231"

--=_p7_disp_2231
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable

The attachment's filename is split into three RFC 2231 segments.
--=_p7_disp_2231
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
 filename*0*=utf-8'de'Quartalsbericht%20;
 filename*1*=Gr%C3%B6%C3%9Fe%20;
 filename*2*=SAMPLE.txt;
 size=69;
 creation-date="Fri, 13 Feb 2026 11:15:00 -0800"

UXVhcnRhbHNiZXJpY2h0IChTQU1QTEUpDQpRMSAyMDI2IHN1cHBseSB2b2x1bWVzLg0KTm8gcmVh
bCBmaWd1cmVzLg0K
--=_p7_disp_2231--

Specifications

Wave
p7
Seed
20260807
Structure
multipart/mixed
Parameter Encoding
RFC 2231
Filename Segments
3
Charset
utf-8
Language
de
Decoded Filename
Quartalsbericht Größe SAMPLE.txt
Size Param
69
Line Endings
CRLF (RFC 5322)

Testing contract

Expected to pass
Scenario
Reassemble an RFC 2231 filename delivered as three numbered, percent-encoded segments carrying charset and language tags.
Expected result
The attachment saves as "Quartalsbericht Größe SAMPLE.txt"; the size parameter matches the decoded part length exactly.

What is a .eml file?

An EML file is a single email message stored in the RFC 822 / MIME format: plain-text headers (From, To, Subject, Date, Message-ID) followed by the body, which may be plain text, HTML, or a multipart structure with alternative bodies and file attachments encoded in base64.

How to use this file

Use an example EML to test email header parsing, MIME decoding, HTML-part handling, attachment extraction, and EML-to-other-format conversion.

How to use this file for testing

“EML: RFC 2231 Continuation Filename With size and creation-date” is a deterministic Testaroo fixture for Email parsing, Encoding detection, Internationalization. Standards-compliant RFC 822 messages (plain, multipart text+HTML, and with an attachment) plus an MBOX mailbox, for testing header parsing, MIME decoding, attachment extraction, and mailbox splitting.

Documented properties for this file: seed 20260807 · de · CRLF (RFC 5322). Compare results against paired or grouped companions on this page when present (clean↔damaged, searchable↔scanned, or format twins) so scores stay reproducible across runs.

Download the file once, keep the path stable in CI or local scripts, and treat the spec table as the contract: dimensions, seeds, field lists, and roles are intentional. Corrupt or invalid samples are labelled as such, expect parsers to fail loudly rather than silently accept them.

Email fixtures use fixed dates, message IDs, and MIME boundaries so runs are reproducible, and every address is fictional. Test header parsing, MIME decoding, attachment extraction, and EML/MBOX conversion against the documented structure.

Code examples

from email import policy
from email.parser import BytesParser

msg = BytesParser(policy=policy.default).parse(open("disposition-rfc2231-continuation.eml", "rb"))
print(msg["subject"], msg["from"])

Generated by generation/email_p7.py. Free for any use, no attribution required, license.

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