A StcsChan is a specialised form of ChannelChannel which supports STC-S I/O operations. Writing an ObjectObject to an StcsChan (using astWriteastWrite) will, if the Object is suitable, generate an STC-S description of that Object, and reading from an StcsChan will create a new Object from its STC-S description.
Normally, when you use an StcsChan, you should provide "source" and "sink" functions which connect it to an external data store by reading and writing the resulting text. These functions should perform any conversions needed between external character encodings and the internal ASCII encoding. If no such functions are supplied, a Channel will read from standard input and write to standard output.
Alternatively, an XmlChanXmlChan can be told to read or write from specific text files using the SinkFileSinkFile and SourceFileSourceFile attributes, in which case no sink or source function need be supplied.
If "source" is NULL and no value has been set for the SourceFile attribute, the StcsChan will read from standard input instead.
If "sink" is NULL, and no value has been set for the SinkFile attribute, the StcsChan will write to standard output instead.