The subscriptions.conf file defines the local subscriptions
that are active. It is normally located in the /etc/cups
directory and is generated automatically by the cupsd(8)
program when subscriptions are created, renewed, or cancelled.
Each line in the file can be a configuration directive, a blank line,
or a comment. Comment lines start with the # character.
DIRECTIVES
<Subscription NNN> ... </Subscription>
Defines a subscription.
Events name [ ... name ]
Specifies the events that are subscribed.
ExpirationTime unix-time
Specifies the expiration time of a subscription as a UNIX time
value in seconds since January 1st, 1970.
Interval seconds
Specifies the preferred time interval for event notifications in
seconds.
JobId job-id
Specifies the job ID associated with the subscription.
LeaseDuration seconds
Specifies the number of seconds that the subscription is valid
for. If 0, the subscription does not expire.
NextEventId number
Specifies the next notify-sequence-number to use for the
subscription.
NextSubscriptionId number
Specifies the next subscription-id to use.
Owner username
Specifies the user that owns the subscription.
PrinterName printername
Specifies the printer or class associated with the subscription.
Recipient uri
Specifies the notify-recipient-uri value for push-type notifications.
UserData hex-escaped-data
Specifies user data to be included in event notifications. This
is typically the "from" address in mailto: notifications.