100 lines
1.8 KiB
Plaintext
100 lines
1.8 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) (argument))
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(do_group
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(command (command_name) (argument))
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(command (command_name) (argument)))))
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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) (argument))
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(command (command_name) (argument) (argument)))
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(command (command_name) (argument))
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(elif_clause
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(pipeline
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(command (command_name) (argument))
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(command (command_name) (argument) (argument)))
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(command (command_name) (argument)))
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(else_clause
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(command (command_name)))))
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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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(quoted_argument (command_substitution (command (command_name))))
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(argument)
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(single_quoted_argument))
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(command (command_name) (argument))))
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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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---
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(program
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(case_statement (quoted_argument)
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(case_item (argument)
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(command (command_name) (argument)))
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(case_item (argument)
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(command (command_name) (argument)))))
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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) (argument))))
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