curl/docs/cmdline-opts/MANPAGE.md

curl man page generator

managen is the curl man page generator. It generates a single nroff man page output from the set of sources files in this directory.

The mainpage.idx file lists all files that are rendered in that order to produce the output. The special %options keyword inserts all command line options documented.

The %options documentation is created with one source file for each supported command line option.

The documentation file format is described below. It is meant to look similar to markdown which is why it uses .md file extensions.

Option files

Each command line option is described in a file named <long name>.d, where option name is written without any prefixing dashes. Like the filename for the -v, --verbose option is named verbose.d.

Each file has a set of meta-data in the top of the file, followed by a body of text.

The documentation files that do not document options have no meta-data part.

A line that starts with <!-- is a comment. It should also end with -->.

Meta-data

--- (start of meta-data)
Added: (version number in which this was added)
Arg: (the argument the option takes)
c: (copyright line)
Example:
  - (an example command line, without "curl" and can use `$URL`)
  - (another example)
Experimental: yes (if so)
Help: (short text for the --help output for this option)
Long: (long form name, without dashes)
Magic: (description of "magic" options)
Multi: single/append/boolean/mutex/custom/per-URL (if used more than once)
Mutexed: (space separated list of options this overrides, no dashes)
Protocols: (space separated list for which protocols this option works)
Requires: (space separated list of features this requires, no dashes)
Scope: global (if the option is global)
See-also:
  - (a related option, no dashes)
  - (another related option, no dashes)
Short: (single letter, without dash)
SPDX-License-Identifier: curl
Tags: (space separated list)
--- (end of meta-data)

Body

The body of the description. Only refer to options with their long form option version, like --verbose. The output generator replaces such option with the correct markup that shows both short and long version.

Text written within *asterisks* is shown using italics. Text within two **asterisks** is shown using bold.

Text that is prefixed with a space is treated like an "example" and gets output in monospace.

Within the body, describe a list of items like this:

## item 1
description

## item 2
second description

The list is automatically terminated at end of file, or you can do it explicitly with an empty "header":

##

Angle brackets (<>) need to be escaped when used in text like \< and \>. This, to ensure that the text renders nicely as markdown.

Headers

The # header can be used by non-option files and it produces a .SH output.

If the # header is used for a command line option file, that header is ignored in the generated output. It can still serve a purpose in the source file as it helps the user identify what option the file is for.

Variables

There are three different "variables" that can be used when creating the output. They need to be written within backticks in the source file (to escape getting spellchecked by CI jobs): %DATE, %VERSION and %GLOBALS.

During rendering, the generator expands them as follows:

• %VERSION -- replaced with the curl version string read from include/curl/curlver.h (e.g. 8.12.0). Can be overridden by setting the CURL_MAKETGZ_VERSION environment variable.
• %DATE -- replaced with the current date in YYYY-MM-DD format, or the date derived from SOURCE_DATE_EPOCH if that environment variable is set (for reproducible builds).
• %GLOBALS -- replaced with a comma-separated list of all command line options that have Scope: global in their meta-data.

Generate

managen mainpage [list of markdown option file names]

This command outputs a single huge nroff file, meant to become curl.1. The full curl man page.

managen ascii [list of markdown option file names]

This command outputs a single text file, meant to become curl.txt. The full curl man page in text format, used to build tool_hugehelp.c.

managen listhelp

Generates a full curl --help output for all known command line options.

Generating the man page

The curl.1 man page is generated from the source files in this directory using the managen Perl script located in scripts/managen. The build system runs this automatically, but it can also be invoked manually.

Prerequisites

The generator requires Perl. The version string is read from include/curl/curlver.h (or from the CURL_MAKETGZ_VERSION environment variable if set). The date defaults to the current date unless SOURCE_DATE_EPOCH is set.

Manual invocation

From the docs/cmdline-opts directory, run:

cd docs/cmdline-opts
perl ../../scripts/managen -I ../../include mainpage ./*.md > curl.1

This produces the complete curl.1 nroff man page. To produce a plain-text version instead, replace mainpage with ascii:

perl ../../scripts/managen -I ../../include ascii ./*.md > curl.txt

The -d flag specifies the directory containing mainpage.idx and the .md option files. The -I flag specifies the include directory root used to locate curl/curlver.h for the version string.

How it works

The generator reads mainpage.idx, which lists the documentation source files in their intended order. Each line names one .md file to render. When the generator encounters the %options keyword in mainpage.idx, it inserts the documentation for every command line option (one .md file per option), sorted alphabetically by long option name.