carta
mkd_in(3)

mkd_in3

Process markdown documents

Part of markdown(3).

Usage

MMIOT

MMIOT

int

Library

Markdown (libmarkdown, -lmarkdown)

Overview

These functions convert Markdown documents and strings into HTML. markdown() processes an entire document, while mkd_text() processes a single string.

To process a file, you pass a FILE* to mkd_in(), and if it returns a nonzero value you pass that in to markdown(), which then writes the converted document to the specified FILE*. If your input has already been written into a string (generated input or a file opened with mmap(2)) you can feed that string to mkd_string() and pass its return value to markdown.()

Markdown() accepts the following flag values (or-ed together if needed) to restrict how it processes input:

MKD_NOLINKS

Don't do link processing, block <a> tags.

MKD_NOIMAGE

Don't do image processing, block <img>.

MKD_NOPANTS

Don't run smartypants().

MKD_NOHTML

Don't allow raw html through AT ALL

MKD_STRICT

Disable superscript and relaxed emphasis.

MKD_TAGTEXT

Process text to put inside an html tag (ID=, NAME=, <title>, &tc); no <em>, no <bold>, no html or [] expansion.

MKD_NO_EXT

Don't allow pseudo-protocols.

MKD_CDATA

Generate code for xml ![CDATA[...]].

MKD_NOSUPERSCRIPT

Don't generate superscripts. Emphasis happens _everywhere_

MKD_NOTABLES

Disallow tables.

MKD_NOSTRIKETHROUGH

Forbid ~~strikethrough~~.

MKD_TOC

Do table-of-contents processing.

MKD_1_COMPAT

Compatibility with MarkdownTest_1.0

MKD_AUTOLINK

Make http://foo.com into a link even without <> s.

MKD_SAFELINK

Paranoid check for link protocol.

MKD_NOHEADER

Don't process header blocks.

MKD_TABSTOP

Expand tabs to 4 spaces.

MKD_NODIVQUOTE

Forbid >%class% blocks.

MKD_NOALPHALIST

Forbid alphabetic lists.

MKD_NODLIST

Forbid definition lists.

MKD_NODLDISCOUNT

Disable the discount definition list syntax style.

MKD_DLEXTRA

Enable the extra definition list syntax style.

MKD_EXTRA_FOOTNOTE

Enable markdown extra-style footnotes.

MKD_NOSTYLE

Do not extract (omit) <style/> blocks from the output.

MKD_FENCEDCODE

Allow fenced code blocks.

MKD_IDANCHOR

Use id= anchors instead of <a name=/> for table-of-contents links.

MKD_GITHUBTAGS

Allow underscore and dash in passed through element names.

MKD_URLENCODEDANCHOR

Use html5 encoding for multibyte and nonalphanumeric characters rather than hex expansion in toc links.

Return values

markdown() returns 0 on success, 1 on failure. The mkd_in() and mkd_string() functions return a MMIOT* on success, null on failure.

Bugs

Error handling is minimal at best.

The MMIOT created by mkd_string() is deleted by the markdown function.

From discount 3.0.2.0-1 in Arch Linux 2026-11-01. Parsed by carta from the page's mdoc source.