BitBake User Manual

Table of Contents

• 1 Overview
  • 1.1 Introduction
  • 1.2 History and Goals
  • 1.3 Concepts
    • 1.3.1 Recipes
    • 1.3.2 Configuration Files
    • 1.3.3 Classes
      • 1.3.3.1 Class Types
    • 1.3.4 Layers
    • 1.3.5 Append Files
  • 1.4 Obtaining BitBake
  • 1.5 The BitBake Command
    • 1.5.1 Usage and syntax
    • 1.5.2 Examples
      • 1.5.2.1 Executing a Task Against a Single Recipe
      • 1.5.2.2 Executing Tasks Against a Set of Recipe Files
      • 1.5.2.3 Executing a List of Task and Recipe Combinations
      • 1.5.2.4 Generating Dependency Graphs
      • 1.5.2.5 Executing a Multiple Configuration Build
      • 1.5.2.6 Enabling Multiple Configuration Build Dependencies
• 2 Execution
  • 2.1 Parsing the Base Configuration Metadata
  • 2.2 Locating and Parsing Recipes
  • 2.3 Providers
  • 2.4 Preferences
  • 2.5 Dependencies
  • 2.6 The Task List
  • 2.7 Executing Tasks
  • 2.8 Checksums (Signatures)
  • 2.9 Setscene
  • 2.10 Logging
• 3 Setting Up The Environment With bitbake-setup
  • 3.1 Quick Start
  • 3.2 Terminology
  • 3.3 The bitbake-setup command
    • 3.3.1 bitbake-setup init
      • 3.3.1.1 bitbake-setup init Examples
    • 3.3.2 bitbake-setup list
    • 3.3.3 bitbake-setup status
    • 3.3.4 bitbake-setup update
      • 3.3.4.1 bitbake-setup update Examples
    • 3.3.5 bitbake-setup install-buildtools
    • 3.3.6 bitbake-setup settings
  • 3.4 Settings
    • 3.4.1 top-dir-prefix
    • 3.4.2 top-dir-name
    • 3.4.3 registry
    • 3.4.4 dl-dir
    • 3.4.5 use-full-setup-dir-name
    • 3.4.6 common-sstate
  • 3.5 Configuration Template Files Reference
    • 3.5.1 Configuration Template Examples
  • 3.6 Source Overrides
  • 3.7 Fixed source revisions
• 4 BitBake Terms
• 5 Syntax and Operators
  • 5.1 Basic Syntax
    • 5.1.1 Basic Variable Setting
    • 5.1.2 Modifying Existing Variables
    • 5.1.3 Line Joining
    • 5.1.4 Variable Expansion
    • 5.1.5 Immediate variable expansion (:=)
    • 5.1.6 Setting a default value (?=)
    • 5.1.7 Setting a weak default value (??=)
    • 5.1.8 Appending (+=) and prepending (=+) With Spaces
    • 5.1.9 Appending (.=) and Prepending (=.) Without Spaces
    • 5.1.10 Appending and Prepending (Override Style Syntax)
    • 5.1.11 Removal (Override Style Syntax)
    • 5.1.12 Override Style Operation Advantages
    • 5.1.13 Variable Flag Syntax
    • 5.1.14 Inline Python Variable Expansion
    • 5.1.15 Unsetting variables
    • 5.1.16 Providing Pathnames
  • 5.2 Exporting Variables to the Environment
  • 5.3 Conditional Syntax (Overrides)
    • 5.3.1 Conditional Metadata
    • 5.3.2 Key Expansion
    • 5.3.3 Examples
  • 5.4 Sharing Functionality
    • 5.4.1 inherit Directive
    • 5.4.2 inherit_defer Directive
    • 5.4.3 include Directive
    • 5.4.4 include_all Directive
    • 5.4.5 require Directive
    • 5.4.6 INHERIT Configuration Directive
    • 5.4.7 addfragments Directive
    • 5.4.8 Locating Include Files
    • 5.4.9 Locating Class Files
  • 5.5 Functions
    • 5.5.1 Shell Functions
      • 5.5.1.1 Limitations
    • 5.5.2 BitBake-Style Python Functions
    • 5.5.3 Python Functions
    • 5.5.4 BitBake-Style Python Functions Versus Python Functions
    • 5.5.5 Anonymous Python Functions
    • 5.5.6 Flexible Inheritance for Class Functions
  • 5.6 Tasks
    • 5.6.1 Promoting a Function to a Task
    • 5.6.2 Deleting a Task
    • 5.6.3 Passing Information Into the Build Task Environment
  • 5.7 Variable Flags
  • 5.8 Events
  • 5.9 Variants — Class Extension Mechanism
  • 5.10 Dependencies
    • 5.10.1 Dependencies Internal to the .bb File
    • 5.10.2 Build Dependencies
    • 5.10.3 Runtime Dependencies
    • 5.10.4 Recursive Dependencies
    • 5.10.5 Inter-Task Dependencies
  • 5.11 Functions You Can Call From Within Python
    • 5.11.1 Functions for Accessing Datastore Variables
    • 5.11.2 Other Functions
    • 5.11.3 Extending Python Library Code
    • 5.11.4 Testing and Debugging BitBake Python code
  • 5.12 Task Checksums and Setscene
  • 5.13 Wildcard Support in Variables
• 6 Variable Context
  • 6.1 BitBake’s own configuration
  • 6.2 BitBake configuration
  • 6.3 Layers and files
  • 6.4 Recipes and packages
• 7 File Download Support
  • 7.1 The Download (Fetch)
  • 7.2 The Unpack
  • 7.3 The Non-Destructive Update (unpack_update)
  • 7.4 Fetchers
    • 7.4.1 Local file fetcher (file://)
    • 7.4.2 HTTP/FTP wget fetcher (http://, ftp://, https://)
    • 7.4.3 Subversion (SVN) Fetcher (svn://)
    • 7.4.4 Git Fetcher (git://)
    • 7.4.5 Git Submodule Fetcher (gitsm://)
    • 7.4.6 ClearCase Fetcher (ccrc://)
    • 7.4.7 Perforce Fetcher (p4://)
    • 7.4.8 Repo Fetcher (repo://)
    • 7.4.9 Az Fetcher (az://)
    • 7.4.10 GCP Fetcher (gs://)
    • 7.4.11 Crate Fetcher (crate://)
    • 7.4.12 NPM Fetcher (npm://)
    • 7.4.13 NPM shrinkwrap Fetcher (npmsw://)
    • 7.4.14 Other Fetchers
  • 7.5 Auto Revisions
  • 7.6 Multiple Source Control Repositories
• 8 Variables Glossary
• 9 Library Functions
  • 9.1 Logging utilities
    • debug()
    • error()
    • erroronce()
    • fatal()
    • note()
    • plain()
    • verbnote()
    • warn()
    • warnonce()
  • 9.2 bb.build
    • addtask()
    • deltask()
    • exec_func()
  • 9.3 bb.utils
    • approved_variables()
    • break_hardlinks()
    • build_environment()
    • check_system_locale()
    • clean_environment()
    • contains()
    • contains_any()
    • copyfile()
    • disable_network()
    • edit_bblayers_conf()
    • edit_metadata()
    • edit_metadata_file()
    • empty_environment()
    • environment()
    • exec_flat_python_func()
    • explode_dep_versions()
    • explode_dep_versions2()
    • explode_deps()
    • fileslocked()
    • filter()
    • filter_environment()
    • filter_string()
    • get_file_layer()
    • get_referenced_vars()
    • goh1_file()
    • is_local_uid()
    • is_path_on_nfs()
    • is_semver()
    • join_deps()
    • landlock_restrict_network()
    • lockfile()
    • md5_file()
    • mkdirhier()
    • mkstemp()
    • movefile()
    • path_is_descendant()
    • preserved_envvars()
    • preserved_envvars_exported()
    • profile_function()
    • prune_suffix()
    • prunedir()
    • remove()
    • sha1_file()
    • sha256_file()
    • sha384_file()
    • sha512_file()
    • signal_on_parent_exit()
    • split_version()
    • to_boolean()
    • to_filemode()
    • umask()
    • unlockfile()
    • vercmp_string()
    • vercmp_string_op()
    • which()
• 10 Hello World Example
  • 10.1 BitBake Hello World
  • 10.2 Obtaining BitBake
  • 10.3 Setting Up the BitBake Environment
  • 10.4 The Hello World Example

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