SCM_API SCM scm_set_port_column_x (SCM port, SCM line);
SCM_API SCM scm_port_filename (SCM port);
SCM_API SCM scm_set_port_filename_x (SCM port, SCM filename);
-SCM_INTERNAL const char *scm_i_get_port_encoding (SCM port);
+SCM_INTERNAL const char *scm_i_default_port_encoding (void);
+SCM_INTERNAL void scm_i_set_default_port_encoding (const char *);
SCM_INTERNAL void scm_i_set_port_encoding_x (SCM port, const char *str);
SCM_API SCM scm_port_encoding (SCM port);
SCM_API SCM scm_set_port_encoding_x (SCM port, SCM encoding);