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42 lines
731 B
Plaintext
42 lines
731 B
Plaintext
---
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syntax: markdown
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tags: [tldr, common]
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source: https://github.com/tldr-pages/tldr.git
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---
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# $
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> Expand a Bash variable.
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> More information: <https://gnu.org/software/bash/manual/bash.html#Shell-Variables>.
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- Print a variable:
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`echo ${{VARIABLE}}`
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- Run variable contents as a command:
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`${{VARIABLE}}`
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- Print the exit status of the previous command:
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`echo $?`
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- Print a random number between 0 and 32767:
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`echo $RANDOM`
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- Print one of the prompt strings:
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`echo ${{PS0|PS1|PS2|PS3|PS4}}`
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- Expand with the output of `command` and run it. Same as enclosing `command` in backticks:
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`$({{command}})`
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- List how many arguments the current context has:
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`echo $#`
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- Print out a Bash array:
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`echo ${{{array_name[@]}}}`
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