complete, compgen, compopt: refresh pages (#17638)

Co-authored-by: Dylan <145150333+dmmqz@users.noreply.github.com>

pages/common/compgen.md

@@ -1,15 +1,21 @@
 # compgen
 
-> A built-in command for auto-completion in Bash, which is called on pressing `<Tab>` key twice.
+> Bash built-in command for generating possible completion matches in Bash.
+> Usually used within custom completion functions.
+> See also: `complete`, `compopt`.
 > More information: <https://www.gnu.org/software/bash/manual/bash.html#index-compgen>.
 
-- List all commands that you could run:
+- List all shell built-ins, aliases, functions and executables that you could run:
 
 `compgen -c`
 
-- List all commands that you could run that start with a specified string:
+- List all commands that you could run that start with a specified string and save results to `COMPREPLY`:
 
-`compgen -c {{str}}`
+`compgen -V COMPREPLY -c {{str}}`
+
+- Match against a wordlist:
+
+`compgen -W "{{apple orange banana}}" {{a}}`
 
 - List all aliases:
 
@@ -30,7 +36,3 @@
 - List all users on the system:
 
 `compgen -u`
-
-- Display help:
-
-`compgen --help`

pages/common/complete.md

@@ -1,16 +1,30 @@
 # complete
 
-> Get argument autocompletion to shell commands.
+> Get and set argument autocompletion rules of shell commands in Bash.
+> The specified completions will be invoked when `<Tab>` is pressed in Bash.
+> See also: `compgen`, `compopt`.
 > More information: <https://www.gnu.org/software/bash/manual/bash.html#index-complete>.
 
-- Apply a function that performs autocompletion to a command:
+- Set arguments of a command to autocomplete through a function (completion response is sent in `COMPREPLY` variable):
 
 `complete -F {{function}} {{command}}`
 
-- Apply a command that performs autocompletion to another command:
+- Set arguments of a command to autocomplete through another command (`$1` is the command, `$2` is the argument the cursor is on, and `$3` is the argument preceding the cursor):
 
 `complete -C {{autocomplete_command}} {{command}}`
 
+- Set arguments of a command to autocomplete to shell builtins:
+
+`complete -A builtin {{command}}`
+
 - Apply autocompletion without appending a space to the completed word:
 
 `complete -o nospace -F {{function}} {{command}}`
+
+- List all loaded complete specifications:
+
+`complete -p`
+
+- List loaded complete specifications for a command:
+
+`complete -p {{command}}`

pages/common/compopt.md

@@ -1,12 +1,22 @@
 # compopt
 
 > Print or change the completion options for a command.
-> More information: <https://manned.org/compopt>.
+> `-o` means enabled and `+o` means disabled.
+> See also: `compgen`, `complete`.
+> More information: <https://www.gnu.org/software/bash/manual/bash.html#index-compopt>.
+
+- Print the completion options for given command:
+
+`compopt {{command}}`
+
+- Enable or disable a completion option of a command:
+
+`compopt {{-o|+o}} {{option1}} {{-o|+o}} {{option2}} {{command}}`
 
 - Print the options for the currently executing completion:
 
 `compopt`
 
-- Print the completion options for given command:
+- Enable or disable a completion option of a command:
 
-`compopt {{command}}`
+`compopt {{-o|+o}} {{option1}} {{-o|+o}} {{option2}}`