SoInput(3) on Linux
The text fd3352d447ed, as Debian 7 (Wheezy) shipped it.
The SoInput class is an abstraction of file import functionality. This class takes care of most of the chores of doing data import in Coin. It puts a layer of abstraction over the read operations to make it transparent for the rest of the Coin code whether or not we're reading from a file, from a memory buffer or from stdin.