Envsubst: Difference between revisions

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=Overview=
=Overview=


<tt>envsubst</tt> performs [[Bash_Variables#Variable_Expansion_in_an_Arbitrary_File|environment variable expansion]] in shell-format strings in arbitrary files. No other shell [[Bash Command Line Expansion#Overview|command line expansions]] will be. performed.
<tt>envsubst</tt> performs [[Bash_Variables#Variable_Expansion_in_an_Arbitrary_File|environment variable expansion]] in shell-format strings in arbitrary files. No other shell [[Bash Command Line Expansion#Overview|command line expansions]] will be. performed. If a variable is declared but not found in the environment, it will be replaced with the empty string.


If a variable is declared but not found in the environment, it will be replaced with the empty string.
cat file.txt | envsubst > file-with-variables-expanded.txt


=Installation=
=Installation=

Revision as of 17:22, 5 May 2018

Internal

Overview

envsubst performs environment variable expansion in shell-format strings in arbitrary files. No other shell command line expansions will be. performed. If a variable is declared but not found in the environment, it will be replaced with the empty string.

cat file.txt | envsubst > file-with-variables-expanded.txt

Installation

Mac

brew install gettext

then modify .bashrc:

 export PATH=/usr/local/opt/gettext/bin:${PATH}

RedHat/Centos