39.6 SRFI-6 - Basic String Ports

SRFI-6 defines the procedures open-input-string, open-output-string and get-output-string. These procedures are included in the Guile core (see String Ports), so using this module does not make any difference at the moment. But it is possible that support for SRFI-6 will be factored out of the core library in the future, so using this module does not hurt, after all.