journalctl:tldr:e8939

The command "journalctl -b --priority=${3}" is used to view the system logs (also known as the journal) with a specific log priority level starting from the current boot.

Here is the breakdown of the command:

• "journalctl": This is the main command for accessing and reading the systemd journal.
• "-b": Specifies that the logs should be shown from the current boot session only.
• "--priority=${3}": The "--priority" option is used to filter the logs based on their priority or severity level. The value "${3}" is a placeholder that implies passing an argument to the command when executing it, such as "--priority=3". The actual value determines the severity level that should be displayed. The severity levels range from 0 to 7, where 0 is the highest severity (emergencies) and 7 is the lowest severity (debug messages).

In summary, running this command will display the system logs with a specific severity level starting from the current boot, where the level is determined by the argument passed with "--priority".