If several lines are available, a Windows CE–based application can open one or more telephone lines for outbound calls. The lineGetDevCaps function queries a specified line device to determine its capabilities. The data returned is valid for all line device addresses. This function determines if the line supports functions that are required in order for calls to be made.
An application can open several instances of a line; in other words, an application can obtain more than one handle to the same line. After a line is selected, the application uses the lineOpen, function to open the specified line.