(v13) Plugin channel device type, 15

This page applies to Harlequin v13.1r0 and later; both Harlequin Core and Harlequin MultiRIP.

The GUI RIP uses device type 15 to communicate with all file-like input plugin channel classes (it also uses type 16 for plugin filters—see Filters —and type 17 for progress reporting plugins—see [HQPLUGIN]).

Plugin channels created using the Input Controller are automatically mounted when first used as the source of a job. (This is done using the file Config/Inputs which uses the procset HqnPluginIO.)

However, you must mount PostScript-managed channels explicitly (also see [HQPLUGIN]). All such mounts must include the device parameter ChannelClass:

ChannelClass (device param)

string

The name of the channel class in a plugin with which the device is to be associated. This name must have been exported by one of the plugins in a ChannelClassDescription structure for setdevparams to succeed.

Additional parameters are specific to each channel class. However, because the core-RIP sees ChannelClass and all the other parameters of the specific channel class simply as parameters of a type 15 device, there is no guarantee that ChannelClass is delivered to the device before any other class-specific paraMinor editsmeters if they are all included in one call of setdevparams. Therefore, it is necessary to defer initialization of any class-specific parameters to a second call of setdevparams.

Consider a type 15 plugin device that we want to call %HQN_modem% and that was implemented with a single class-specific string parameter PhoneNumber. The mount sequence looks like this:

            (%HQN_modem%) dup devmount pop dup <<
            /DeviceType 15
            /Enable true
            /SearchOrder -1
            /ChannelClass (HQN_DialUp)
            >> setdevparams
            <<
            /PhoneNumber (+44 1223 872519)
            >> setdevparams

To avoid name clashes, we recommend using your company name or OEM number in the device names and channel class names, as in the example above.