Mbox Meson Ref May 2026

1. MBOX – Email Storage Format

2. Meson – Build System

Meson build files

Top-level meson.build:

• Project declaration, version, C standard, default_options for warning flags.
• add_subdir('src')
• add_subdir('examples')
• add_subdir('tests')
• install include files from include/mbox_ref

src/meson.build:

• libmbox = library('mbox_ref', ['mbox.c', 'ref.c'], include_directories: include_directories('../include'))
• install_headers(['../include/mbox_ref/mbox.h', '../include/mbox_ref/ref.h'], subdir: 'mbox_ref')
• Declare static_library or shared depending on option.

examples/meson.build:

• executable('show-mbox', 'show-mbox.c', link_with: libmbox)
• run the example in CI or via meson test if desired.

tests/meson.build:

• Use meson.get_compiler('c').find_library('munit') or use simple test runner.
• test executable 'test_mbox' built with test_mbox.c linked to libmbox
• meson.add_test('basic', test_exe)

Meson tips:

• Set default_options: ['buildtype=debugoptimized', 'warning_level=3']
• Provide option('buildshared', type: 'boolean', value: true, description: 'Build shared library')
• Use dependency('glib-2.0') only if you want advanced parsing utilities; keep pure C stdlib to minimize dependencies.
• Use meson.override_dependency for CI when mocking optional deps.
• For packaging, create meson wrap or provide simple install rules; use meson install to place headers and library in correct prefix.

4. Intersections of MBOX, Meson, and REF

No direct standard combination exists, but plausible scenarios:

Step 2: Adding a Reference Inside an Equation

To cite a paper or a table directly inside a mathematical expression: mbox meson ref

\[
\Gamma_D_s^*+ = 0.95 \pm 0.03 \ \mbox(Ref.~\citePDG)
\]

1.1 Definition

MBOX is a family of file formats used to store collections of email messages in a single plain text file. Each message is concatenated and separated by a “From ” line (often called “From_ line”).

Troubleshooting common issues

• Large files and 32-bit offsets: ensure large-file support macros (e.g., _FILE_OFFSET_BITS=64) or use platform-specific APIs.
• Character encodings: mbox is byte-oriented; headers may use MIME encodings (=?UTF-8?Q?...?). For presentation decode MIME encoded-words using a helper or library.
• Locked mailboxes: some systems append with exclusive locks; for read-only parsing you typically only need shared read access.

1.2 Common Variants

• MBOXO (classic): Used by Unix mail and older systems. Separator begins with From followed by the sender’s address and timestamp.
• MBOXRD (or MBOXCL): Used by Qmail and others; uses From but also >From escaping.
• MBOXCL2: Used by some newer clients; stricter escaping rules.

Core parsing approach

1. Open file with fopen(); use fseek/ftell to scan.
2. Find messages by locating lines starting with "From " at the beginning of a line.
3. Record message start offset (first line after "From ..." header) and end offset (just before next "From " or EOF).
4. For each message, on-demand parse headers by seeking to start and reading until blank line that separates headers and body.
5. Extract headers by scanning lines, handling folded headers (lines beginning with space or tab belong to previous header).
6. Body length = end-start - headers_len.
7. Expose a Ref that contains offsets and small cached strings for common headers (Subject, From, Date) to avoid reparsing repeatedly.

Caveats: This simple parser does not fully implement all RFC-5322 edge cases (e.g., nested message/rfc822 attachments, complex encodings). Mention that for production an RFC-compliant parser or lib (libmapi, gmime) may be preferable. src/meson