Purpose: To get TclX file functionality into the core.
The -keepalive option should be added to fconfigure for sockets
A new command pipe should be added to provide TclX pipe functionality.
Changes to tcl's file command
A new file type result, tty, will be added.
a new file option -fileid to allow an open file to be processed in place of the file name argument. (This may not be possible under windows.)