C Quirk??

[Rich Salz]

=>>#define               clearline()             while (getchar() != '\n')
=> This is seriously bad code.  What if stdin reaches end of file?
=
=   It loops forever -- oops.  Change that to 
=#define clearline() while (1) {int ch = getchar(); \
=                         if ((ch == EOF) || (ch =='\n')) break; }

Not quite yet; the following "obvious" fragment won't compile
(try it before posting "why" to the net):
	if (a)
	    if (b)
		clearline();
	    else
		printf("Don't know about b, but a is zero.\n");

This should work:
#define clearline() \
	while (getchar() != '\n' && !feof(stdin) && !ferror(stdin))

As a general rule, you probably don't want to use { } in #define's
as  { }; is not the same as { }.
	/r$
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