[CM] Bug in read

[bil at ccrma.Stanford.EDU]

I need to look at this more closely, but at least
in this case, you can fix it by changing lines 28669:

#if 0
       if (*str != 0)
	port_position(pt) += (k - 1);
       else port_position(pt) += k;
#else
       port_position(pt) += (k - 1);
#endif

This passes s7test.scm, but I'm currently still running my
main tests.