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The SCOadmin framework provides support for all the SCOadmin capabilities that are not related to the user interface, such as networked object programming, error handling, and internationalization. Its functions can be accessed from the libsysadm.a library by C and C++ programs and directly from osavtcl for Tcl programs.
The object client API described in ``About SCOadmin objects'' allows objects to be created, manipulated, and deleted. For example, the ObjectGet(TCL_ADM) call can be used to get the attributes of either a printer or a filesystem. The request is carried out by an object service agent (OSA) for the particular class of object. It is up to the OSA writer to define the characteristics of a class of objects and to interpret the semantics of operations on objects of that class.
A SCOadmin manager has the capability to access managed objects on the local system or on any remote system which has SCOadmin installed. When a manager wishes to perform an object operation, it makes a call to the framework with the name and class of the object upon which it wishes to operate, along with any other information needed for the object request. If the framework determines that the object request is for an object on another system, it forwards the request to a framework running there. In either the local or the remote case, the framework finds out the OSA associated with the requested object and passes the request to it. The OSA (which can be either a Tcl or C program) interprets the request and sends back a response, which gets sent back to the caller. The OSA/manager interface is based on the Open System Interconnect management protocol called Common Management Information Protocol (CMIP). SCOadmin uses a simplified version called Basic Management Information protocol (BMIP). The framework contains many helper functions to extract and manipulate BMIP information so that managers and OSAs do not have to deal directly with the protocol.