systemd-cat_command_examples
systemd-cat – Connect a pipeline or program’s output with the journal
Example 1. Invoke a program
This calls /bin/ls with standard output and error connected to the journal:
# systemd-cat ls
Example 2. Usage in a shell pipeline
This builds a shell pipeline also invoking /bin/ls and writes the output it generates to the journal:
# ls | systemd-cat
Even though the two examples have very similar effects the first is preferable since only one process is running at a time, and both stdout and stderr are captured while in the second example, only stdout is captured.