A connector is a software representation of the physical way in which multimedia data moves from one device to another. Simple examples are the headphone jack on a CD-ROM player, or the speakers jack on an audio adapter. If an audio card has both a speaker and a line OUT jack, it is desirable to let an application choose the destination of the audio, while remaining independent from the actual hardware implementation.
OS/2 multimedia connectors provide this function by allowing an application to query which connectors are supported by a logical device, and manipulate whether or not information is flowing through the connector. The connectors for a logical device can be accessed either by number or by a symbolic connector type. When specifying a symbolic type such as microphone or line IN, a number can also be specified to select the first connector, second connector, and so on, of that specific connector type. The MCI_CONNECTORINFO message can be used to determine which connectors are supported by a device, whereas the MCI_CONNECTOR message can be used to enable, disable, or query the state of a particular connector.
Although connectors are typically associated with the representation of externally visible audio and video jacks on multimedia equipment, another category of connectors can represent the flow of information within a computer. For example, a connector on an audio adapter can be attached to the internal PC speaker. A more subtle example is the flow of digital audio information into an audio adapter. This information could come from a file, system memory, or another device. Connectors of this category are referred to as stream connectors to convey the idea of a logical stream of information flowing from one device to another.