ScmPortError      184 src/error.c        ScmPortError *e = SCM_ALLOCATE(ScmPortError, klass);
ScmPortError      160 src/gauche/exception.h #define SCM_PORT_ERROR(obj)      ((ScmPortError*)(obj))
ScmPortError      166 src/gauche/exception.h typedef ScmPortError ScmIOReadError;
ScmPortError      167 src/gauche/exception.h typedef ScmPortError ScmIOWriteError;
ScmPortError      168 src/gauche/exception.h typedef ScmPortError ScmIOClosedError;
ScmPortError      169 src/gauche/exception.h typedef ScmPortError ScmIOUnitError;