envsubst:tldr:db1ea

envsubst: Replace environment variables in `stdin` and output to `stdout`.

echo

$ echo '${$HOME}' | envsubst

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This command is used to substitute the value of the $HOME environment variable within a string by using the envsubst command.

The echo '${$HOME}' part of the command prints the string '$HOME' to the standard output. The single quotes around $HOME ensure that the variable is not expanded by the shell during the echo command.

The output of the echo command ('$HOME') is then piped (|) to the envsubst command. envsubst is a command-line utility that substitutes the values of environment variables found in a string. In this case, it will substitute the value of the $HOME environment variable within the string '$HOME'.

The envsubst command receives the string '$HOME' through the standard input and replaces the $HOME with the value of the actual $HOME environment variable. For example, if the value of $HOME is /home/example, the output of the command will be /home/example.

So, the overall purpose of this command is to replace the $HOME placeholder in the string with the actual value of the $HOME environment variable.

This explanation was created by an AI. In most cases those are correct. But please always be careful and never run a command you are not sure if it is safe.

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