atuin:tldr:a3916

This command is using the eval command in combination with command substitution ($(atuin init ${select})).

The eval command in bash is used to evaluate and execute the given arguments as a shell command. It takes the arguments, concatenates them into a single command, and then executes that command.

The command substitution part, $(atuin init ${select}), is enclosed within $() which means that the output of the command inside the parentheses is substituted in place. So, the command atuin init ${select} is executed, and its output is used as part of the evaluated command.

To break it down further:

• ${select} is a variable being passed as an argument to the atuin init command.
• atuin is likely the name of a program or script that is being called.
• init is an argument being passed to the atuin command to execute some initialization process.

Overall, this command executes the atuin command with the init argument, passed with the value of the ${select} variable, and then evaluates the resulting command.