ATM Configuration and Management Manual

SCF Commands
ATM Configuration and Management Manual—522307-003
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SCF Objects
SCF performs most commands in the following sequence:
1. When SCF receives a command, it interprets the command and performs the
necessary steps to execute it. Some commands can be handled by SCF with no
interaction with SCP (for example, VOLUME and OUT).
2. If the command involves control or configuration of an object or a request for
information about an object, SCF produces an SPI message that describes the
object and the operation to be performed on it. This message goes to a subsystem
I/O process or a subsystem manager process through SCP. A single command
might require several SPI messages before the operation can be completed. The
exact number of steps required to execute a command varies from subsystem to
subsystem and from command to command.
3. When the subsystem I/O process or subsystem manager process has processed
the message, it returns a completion message to SCF through SCP. If the
message indicates a successful completion, SCF displays its prompt and waits for
the next command. If the completion message indicates an exception condition,
SCF displays an appropriate message, then displays its prompt.
SCF Objects
The individual components of SCF subsystems are called objects. Each object has an
object type and an object name. The object type describes the type of the object, such
as SU (subdevice), DISK, or PROCESS. The object name uniquely identifies an object
within the system.
Object names usually follow a consistent set of naming conventions. SCF objects are
referred to by their device names, which consist of a dollar sign ($) followed by a letter
and several alphanumeric characters. The number of characters is determined by the
subsystem. A LINE object, for example, might have the name $LIN32. A PROCESS
object sometimes has the same name as the line it controls. For more information
about objects, see the SCF Reference Manual for G-Series RVUs .
Many other object types and object names are used in SCF. The objects relevant to the
ATM subsystem are described later in this section.