33 lines
582 B
Markdown
33 lines
582 B
Markdown
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# Dollar sign
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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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- 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 ${{PS0|PS1|PS2|PS3|PS4}}`
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- Expand with the output of `command` and run it. Same as enclosing `command` in backtics:
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`$({{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[@]}`
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