systemd-cat:tldr:84376

The command "${command} | systemd-cat" is a combination of two separate commands, separated by the pipe symbol (|), which is used for command chaining in a Unix-based shell.

1. "${command}" represents a placeholder for any command or executable that you would like to run. You would replace "${command}" with your intended command.

2. "|" is the pipe symbol, which is used to take the output of the preceding command and pass it as input to the following command.

3. "systemd-cat" refers to a built-in Linux command for sending standard input or error messages to the systemd journal. It redirects the output (both standard output and standard error) of the preceding command to the systemd journal, allowing you to log and monitor the command's output using systemd tools.

So, when you use the "${command} | systemd-cat" format, the output of the specified command will be logged and can be accessed later using systemd journal tools for troubleshooting and monitoring purposes.