RI(1) UNIX RI(1)

# [NAME](#NAME)

**ri** - Ruby API reference front end

# [SYNOPSIS](#SYNOPSIS)

**ri** \[**-ahilTv**] \[**-d** *DIRNAME*] \[**-f** *FORMAT*] \[**-w** *WIDTH*] \[**--**\[**no-**]**pager**] \[**--server**\[=*PORT*]] \[**--**\[**no-**]**list-doc-dirs**] \[**--no-standard-docs**] \[**--**\[**no-**]{**system**|**site**|**gems**|**home**}] \[**--**\[**no-**]**profile**] \[**--dump**=*CACHE*] \[*name* ...]

# [DESCRIPTION](#DESCRIPTION)

**ri** is a command-line front end for the Ruby API reference. You can search and read the API reference for classes and methods with **.**

**ri** is a part of Ruby.

*name* can be: It Class | Module | Module::Class

It Class::method | Class#method | Class.method | method

It gem\_name: | gem\_name:README | gem\_name:History

All class names may be abbreviated to their minimum unambiguous form. If a name is ambiguous, all valid options will be listed.

A \`.' matches either class or instance methods, while #method matches only instance and ::method matches only class methods.

README and other files may be displayed by prefixing them with the gem name they're contained in. If the gem name is followed by a \`:' all files in the gem will be shown. The file name extension may be omitted where it is unambiguous.

For example:

ri Fil  
ri File  
ri File.new  
ri zip  
ri rdoc:README

Note that shell quoting or escaping may be required for method names containing punctuation:

ri 'Array.\[]'  
ri compact\\!

To see the default directories **ri** will search, run:

ri --list-doc-dirs

Specifying the **--system**,**--site**,**--home**,**--gems**, or **--doc-dir** options will limit **ri** to searching only the specified directories.

**ri** options may be set in the *RI* environment variable.

The **ri** pager can be set with the *RI\_PAGER* environment variable or the *PAGER* environment variable.

# [OPTIONS](#OPTIONS)

[**-i**](#i)

**--**\[**no-**]**interactive**

In interactive mode you can repeatedly look up methods with autocomplete.

[**-a**](#a)

**--**\[**no-**]**all**

Show all documentation for a class or module.

[**-l**](#l)

**--**\[**no-**]**list**

List classes **ri** knows about.

**--**\[**no-**]**pager**

Send output to a pager, rather than directly to stdout.

[**-T**](#T)

Synonym for **--no-pager**.

[**-w** *WIDTH*](#w)

[**--width**=*WIDTH*](#width)

Set the width of the output.

[**--server**\[=*PORT*\]](#server)

Run RDoc server on the given port. The default port is 8214.

[**-f** *FORMAT*](#f)

[**--format**=*FORMAT*](#format)

Use the selected formatter. The default formatter is bs for paged output and ansi otherwise. Valid formatters are: ansi,bs,markdown,rdoc.

[**-h**](#h)

[**--help**](#help)

Show help and exit.

[**-v**](#v)

[**--version**](#version)

Output version information and exit.

Data source options:

**--**\[**no-**]**list-doc-dirs**

List the directories from which **ri** will source documentation on stdout and exit.

[**-d** *DIRNAME*](#d)

[**--doc-dir**=*DIRNAME*](#doc_dir)

List of directories from which to source documentation in addition to the standard directories. May be repeated.

[**--no-standard-docs**](#no_standard_docs)

Do not include documentation from the Ruby standard library, *site\_lib*, installed gems, or *~/.rdoc*. Use with **--doc-dir**.

**--**\[**no-**]**system**

Include documentation from Ruby's standard library. Defaults to true.

**--**\[**no-**]**site**

Include documentation from libraries installed in *site\_lib*. Defaults to true.

**--**\[**no-**]**gems**

Include documentation from RubyGems. Defaults to true.

**--**\[**no-**]**home**

Include documentation stored in *~/.rdoc*. Defaults to true.

Debug options:

**--**\[**no-**]**profile**

Run with the Ruby profiler.

[**--dump**=*CACHE*](#dump)

Dump data from an ri cache or data file.

# [ENVIRONMENT](#ENVIRONMENT)

[**RI**](#RI)

Options to prepend to those specified on the command-line.

[**RI\_PAGER**](#RI_PAGER)

[**PAGER**](#PAGER)

Pager program to use for displaying.

[**HOME**](#HOME)

[**USERPROFILE**](#USERPROFILE)

[**HOMEPATH**](#HOMEPATH)

Path to the user's home directory.

# [FILES](#FILES)

**~/.rdoc**

Path for ri data in the user's home directory.

# [SEE ALSO](#SEE_ALSO)

[**ruby**(1)](/man/os/ruby-3.4/ruby.1), [**rdoc**(1)](/man/os/ruby-3.4/rdoc.1), [**gem**(1)](/man/os/ruby-3.4/gem.1)

# [REPORTING BUGS](#REPORTING_BUGS)

- Security vulnerabilities should be reported via an email to Mt security@ruby-lang.org. Reported problems will be published after being fixed.
- Other bugs and feature requests can be reported via the Ruby Issue Tracking System (**https://bugs.ruby-lang.org/**). Do not report security vulnerabilities via this system because it publishes the vulnerabilities immediately.

# [AUTHORS](#AUTHORS)

Written by Dave Thomas <dave@pragmaticprogrammer.com>.

Ruby Programmer's Reference Guide April 20, 2017

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Document: ri(1) from ruby-3.4 3.4.12-r1 (Chainguard OS)
Source: https://github.com/ruby/ruby