Author: Stan Eisenstat
Subject: isspace()
Date: Tuesday, 28 Jan 2020, 14:51:57

The function isspace(int c) returns a nonzero value if
its argument c is a white-space character (that is, a
space (' '), form-feed ('\f'), newline ('\n'), carriage
return ('\r'), horizontal tab ('\t'), or vertical tab
('\v'); and zero otherwise.

Some of the tests (for example, Test #02) contain tabs
as well as spaces.  If your Cxref tests for spaces(*),
it should probably be using isspace() instead.

  (*) Hwk1/Cxref never checks whether a character is
      white-space, so it did not occur to me to mention this
      function in the specification.

--Stan-