Implementing built-ins (POSIX portability)

[magicant]

This issue tracks minimum POSIX-compliant implementation of built-in utilities.
Non-portable features are tracked in #265.

In the list below, built-ins are grouped by their dependent environments.
However, most built-ins additionally depend on the standard output and error file descriptors and variables.

Nop

• :
  • Colon built-in #322
• true
  • 3d3fe8e
• false
  • 854b7ff

Execution control

• .
  • Source built-in #324
• break
  • Break built-in #188
• continue
  • Continue built-in #189
• eval
  • Eval built-in #323
• exec
  • Implementing exec built-in (POSIX portability) #231
• exit
  • Implement exit built-in (POSIX portability) #266
  • Default exit status in trap #268
• newgrp
• return
  • Basic return built-in semantics #271

Working directory

• cd
  • Implement cd built-in #284
• pwd
  • Implement pwd built-in #278

File creation mask

• umask
  • Umask built-in #354

Limits

• ulimit
  • Ulimit built-in #355

Spent times

• times
  • Times built-in #351

Signals

• kill
  • Kill built-in #346
• trap
  • Trap built-in (POSIX requirements) #337

Jobs

• bg
  • Fg & bg built-ins #339
• fg
  • Fg & bg built-ins #339
• jobs
  • Implementing jobs built-in (POSIX portability) #155
• wait
  • Implementing wait built-in #152

Variables and functions

• export
  • Export built-in #319
• getopts
  • Getopts built-in #326
• read
  • Read built-in #327
• readonly
  • Readonly builtin #320
• shift
  • Shift built-in #305
• unset
  • Unset built-in #301

Aliases

• alias
  • Alias built-in #328
• unalias
  • Unalias built-in (POSIX only) #329

Command path cache

• hash
  • Hash built-in
    • Show cached utilities
    • Update utility path cache
    • Clear utility path cache

Command history

• fc
  • Fc built-in
    • Semantics
      • Show command history
      • Edit and execute a command from history
    • Portable options
      • -e ...
      • -l
      • -n
      • -r
      • -s

Miscellaneous

• command, type (Mostly related with execution control, but also dependent on file system, aliases, functions, and command path cache)
  • Command built-in (POSIX portability) #347
    • Extend support for confstr on more systems
  • Type built-in #350
• set (Related with shell options and variables)
  • Implementing set built-in #149