User`s guide

3-5
Spooler Overview
• Diablo 630
• ditroff
Printer Devices
A printer/plotter device is a special file in the /dev/directory for a real printer. This file can
be used by redirection (for example, cat FileName > /dev/lp0) or by user–written, compiled
programs. Settings for this device driver can be displayed and changed using the splp
command. Before any of the spooler commands can access a printer device, a print queue
must be created for the device.
qdaemon
The qdaemon is a process that runs in the background under the auspices of the srcmstr
process. When you turn your system on, the startsrc command starts the qdaemon. While
the qdaemon can be started by the startsrc command or stopped by the stopsrc
command, the qdaemon supports only signal communications and thus cannot be queried
by the lssrc command.
The qdaemon tracks both job requests and the resources necessary to complete the jobs,
where the resources may be a real printer, some other real device, or even a file. The
qdaemon maintains queues of outstanding requests and sends them to the proper device
at the proper time. The qdaemon also records printer usage data for system accounting
purposes. It is the qdaemon that sets the backend for a spooler queue into execution.
If the qdaemon is aborted, it will be restarted by srcmstr.
Note: Please do not attempt to stop the srcmstr daemon; it controls other daemons
running on your system.