We have now seen all essential printer commands, but how can we find out what printers there are and what they are doing.
UNIX provides the lpc
command
to do exactly that. Additionally it offers the printer administrator
the options to start and stop printing and queueing of new jobs. The
administrator can also rearrange the order of the jobs in the queue.
The lpc command can either be run as an interactive program or by supplying lpc with commands on the command line:
$lpc
lpc> help
Commands may be abbreviated. Commands are:
abort enable disable help restart status topq ?
clean exit down quit start stop up
lpc> status
ascii:
queuing is enabled
printing is enabled
1 entry in spool area
waiting for ascii to become ready (offline ?)
lp:
queuing is enabled
printing is enabled
1 entry in spool area
lp is ready and printing
raw:
queuing is enabled
printing is enabled
no entries
no daemon present
lpc> quit
$lpc status
ascii:
queueing is enabled
printing is enabled
1 entry in spool area
waiting for ascii to become ready (offline ?)
lp:
queueing is enabled
printing is enabled
1 entry in spool area
lp is ready and printing
raw:
queueing is enabled
printing is enabled
no entries
no daemon present
$
We can see which printers there are on the system, if they are printing and accepting jobs, how many jobs there are in the print queue and what the printers status is. The additional commands displayed by the help command are only available to the administrator.