2018-04-12 17:39:43 +01:00
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# envsubst
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2019-08-07 06:32:59 +01:00
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> Substitutes environment variables with their value in shell format strings.
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> Variables to be replaced should be in either `${var}` or `$var` format.
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2021-04-17 16:15:37 +01:00
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> More information: <https://www.gnu.org/software/gettext/manual/html_node/envsubst-Invocation.html>.
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2018-04-12 17:39:43 +01:00
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2021-01-31 17:05:18 +00:00
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- Replace environment variables in stdin and output to stdout:
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2018-04-12 17:39:43 +01:00
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`echo '{{$HOME}}' | envsubst`
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2021-01-31 17:05:18 +00:00
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- Replace environment variables in an input file and output to stdout:
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2018-04-12 17:39:43 +01:00
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2019-08-07 06:32:59 +01:00
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`envsubst < {{path/to/input_file}}`
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2018-04-12 17:39:43 +01:00
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- Replace environment variables in an input file and output to a file:
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2019-08-07 06:32:59 +01:00
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`envsubst < {{path/to/input_file}} > {{path/to/output_file}}`
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2018-04-12 17:39:43 +01:00
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2019-08-07 06:32:59 +01:00
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- Replace environment variables in an input file from a space-separated list:
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2018-04-12 17:39:43 +01:00
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2019-08-07 06:32:59 +01:00
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`envsubst '{{$USER $SHELL $HOME}}' < {{path/to/input_file}}`
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