233 lines
4.8 KiB
Plaintext
233 lines
4.8 KiB
Plaintext
=============================
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Literal words
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=============================
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echo a
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echo a b
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---
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(program
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(command (command_name (word)) (word))
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(command (command_name (word)) (word) (word)))
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=============================
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Simple variable expansions
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=============================
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echo $abc
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---
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(program
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(command (command_name (word)) (simple_expansion (variable_name))))
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=============================
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Variable expansions
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=============================
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echo ${abc}
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echo ${abc:-def}
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echo ${abc:- }
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echo ${abc:
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}
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---
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(program
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(command (command_name (word)) (expansion (variable_name)))
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(command (command_name (word)) (expansion (variable_name) (word)))
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(command (command_name (word)) (expansion (variable_name)))
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(command (command_name (word)) (expansion (variable_name))))
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===================================
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Other variable expansion operators
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===================================
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cat ${BAR} ${ABC=def} ${GHI:?jkl}
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---
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(program
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(command
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(command_name (word))
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(expansion (variable_name))
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(expansion (variable_name) (word))
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(expansion (variable_name) (word))))
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=============================
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Command substitutions
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=============================
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echo `echo hi`
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echo $(echo $(echo hi))
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---
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(program
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(command
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(command_name (word))
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(command_substitution (command (command_name (word)) (word))))
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(command
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(command_name (word))
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(command_substitution (command
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(command_name (word))
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(command_substitution (command
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(command_name (word))
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(word)))))))
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=============================
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Process substitutions
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=============================
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wc -c <(echo abc && echo def)
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echo abc > >(wc -c)
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---
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(program
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(command
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(command_name (word))
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(word)
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(process_substitution (list
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(command (command_name (word)) (word))
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(command (command_name (word)) (word)))))
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(command
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(command_name (word))
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(word)
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(file_redirect (process_substitution
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(command (command_name (word)) (word))))))
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=============================
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Single quoted strings
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=============================
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echo 'a b' 'c d'
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---
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(program
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(command (command_name (word)) (raw_string) (raw_string)))
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=============================
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Double quoted strings
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=============================
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echo "a" "b"
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echo "a ${b} c" "d $e"
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---
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(program
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(command (command_name (word))
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(string)
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(string))
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(command (command_name (word))
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(string (expansion (variable_name)))
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(string (simple_expansion (variable_name)))))
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=========================================
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Strings containing command substitutions
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=========================================
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find "`dirname $file`" -name "$base"'*'
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---
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(program
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(command
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(command_name (word))
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(string (command_substitution (command (command_name (word)) (simple_expansion (variable_name)))))
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(word)
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(concatenation
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(string (simple_expansion (variable_name)))
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(raw_string))))
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=========================================
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Variable declaration: declare & typeset
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=========================================
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declare var1
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typeset -i -r var2=42 var3=10
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---
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(program
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(declaration_command (simple_variable_name))
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(declaration_command (argument) (argument)
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(variable_assignment (variable_name) (word))
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(variable_assignment (variable_name) (word))))
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=========================================
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Variable declaration: readonly
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=========================================
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readonly var1
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readonly var2=42
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---
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(program
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(declaration_command (simple_variable_name))
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(declaration_command (variable_assignment (variable_name) (word))))
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=========================================
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Variable declaration: local
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=========================================
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local a=42 b
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local -r c
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---
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(program
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(declaration_command
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(variable_assignment (variable_name) (word))
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(simple_variable_name))
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(declaration_command (argument) (simple_variable_name)))
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=========================================
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Variable declaration: export
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=========================================
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export PATH
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export FOOBAR PATH="$PATH:/usr/foobar/bin"
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---
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(program
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(declaration_command (simple_variable_name))
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(declaration_command
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(simple_variable_name)
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(variable_assignment (variable_name) (string (simple_expansion (variable_name))))))
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=========================================
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Arrays and array expansions
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=========================================
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a=()
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b=(1 2 3)
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echo ${a[@]}
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echo ${#b[@]}
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a[$i]=50
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a+=(foo "bar" $(baz))
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---
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(program
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(variable_assignment (variable_name) (array))
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(variable_assignment (variable_name) (array (word) (word) (word)))
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(command (command_name (word)) (expansion (variable_name)))
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(command (command_name (word)) (expansion (variable_name)))
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(variable_assignment
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(subscript (variable_name) (simple_expansion (variable_name)))
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(word))
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(variable_assignment
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(variable_name)
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(array
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(word)
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(string)
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(command_substitution (command (command_name (word)))))))
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