What is the command used to submit a new print job to print a file?

The command used to submit a new print job to print a file is lpr. This command is part of the Common Unix Printing System (CUPS) and allows users to send files to the printer for printing. When you use lpr followed by a filename, it instructs the system to place the specified file in the print queue.

For context, lpq is a command used to check the current status of the print queue, showing jobs that are waiting to be printed. dmesg displays kernel-related messages for system diagnostics and is unrelated to printing functions. lsblk lists block devices on the system, which is also not associated with submitting print jobs.

Thus, lpr is the appropriate command to initiate the actual printing process by sending the file to the printer.