266 lines
5.3 KiB
Plaintext
266 lines
5.3 KiB
Plaintext
====================================
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While statements
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====================================
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while something happens; do
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echo a
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echo b
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done
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---
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(program
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(while_statement
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(command (command_name (word)) (word))
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(do_group
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(command (command_name (word)) (word))
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(command (command_name (word)) (word)))))
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====================================
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While statements with IO redirects
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====================================
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while read line; do
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echo $line
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done < <(cat file)
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---
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(program
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(while_statement
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(command (command_name (word)) (word))
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(do_group
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(command (command_name (word)) (simple_expansion (variable_name))))
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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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For statements
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====================================
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for a in 1 2 $(seq 5 10); do
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echo $a
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done
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---
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(program
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(for_statement
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(variable_name)
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(word)
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(word)
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(command_substitution (command (command_name (word)) (word) (word)))
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(do_group
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(command (command_name (word)) (simple_expansion (variable_name))))))
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====================================
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If statements
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====================================
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if cat some_file | grep -v ok; then
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echo one
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elif cat other_file | grep -v ok; then
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echo two
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else
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exit
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fi
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---
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(program
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(if_statement
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(pipeline
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(command (command_name (word)) (word))
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(command (command_name (word)) (word) (word)))
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(command (command_name (word)) (word))
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(elif_clause
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(pipeline
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(command (command_name (word)) (word))
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(command (command_name (word)) (word) (word)))
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(command (command_name (word)) (word)))
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(else_clause
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(command (command_name (word))))))
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====================================
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If statements with conditional expressions
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====================================
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if [ "$(uname)" == 'Darwin' ]; then
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echo one
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fi
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---
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(program
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(if_statement
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(bracket_command
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(string (command_substitution (command (command_name (word)))))
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(word)
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(raw_string))
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(command (command_name (word)) (word))))
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====================================
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Case statements
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====================================
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case "opt" in
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a)
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echo a
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;;
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b)
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echo b
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;;
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esac
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case "$Z" in
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ab*|cd*) ef
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esac
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---
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(program
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(case_statement (string)
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(case_item (word)
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(command (command_name (word)) (word)))
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(case_item (word)
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(command (command_name (word)) (word))))
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(case_statement (string (simple_expansion (variable_name)))
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(case_item (word) (word)
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(command (command_name (word))))))
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===============================
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Subshells
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===============================
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(
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./start-server --port=80
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) &
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---
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(program
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(subshell (command (command_name (word)) (word))))
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===============================
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Function definitions
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===============================
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do_something() {
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echo ok
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}
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function do_something_else() {
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echo ok
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}
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function do_yet_another_thing {
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echo ok
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} 2>&1
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---
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(program
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(function_definition
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(word)
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(compound_statement (command (command_name (word)) (word))))
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(function_definition
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(word)
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(compound_statement (command (command_name (word)) (word))))
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(function_definition
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(word)
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(compound_statement (command (command_name (word)) (word)))
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(file_redirect (file_descriptor) (word))))
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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 (variable_name))
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(declaration_command (word) (word)
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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 (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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(variable_name))
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(declaration_command
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(word)
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(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 (variable_name))
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(declaration_command
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(variable_name)
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(variable_assignment (variable_name) (string (simple_expansion (variable_name))))))
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===========================================
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Expressions passed to declaration commands
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===========================================
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export "$(echo ${key} | tr [:lower:] [:upper:])=${p_key#*=}"
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---
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(program
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(declaration_command
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(string
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(command_substitution
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(pipeline
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(command (command_name (word)) (expansion (variable_name)))
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(command (command_name (word)) (concatenation (word)) (concatenation (word)))))
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(expansion (variable_name) (word)))))
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=========================================
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Unset commands
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=========================================
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unset A
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unset "$variable_name"
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unsetenv -f ONE TWO
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---
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(program
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(unset_command (variable_name))
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(unset_command (string (simple_expansion (variable_name))))
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(unset_command (word) (variable_name) (variable_name)))
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