getchar() question in 4.2

[mm1751 at Almsa-1.ARPA]

From:      Mary Mallott <mm1751 at Almsa-1.ARPA>

We recently converted to 4.2 from 4.1 and I had some fairly simple programs
that worked fine before and the compiled versions continued to work fine
under 4.2.  But when I recompiled the same source under 4.2, getchar() seems
to hang on to EOF characters.  If I do getchars and end with ^D, the next 
time (or multiple times) I do either getchar or scanf, it doesn't wait
for input.  It just continues on and the variables read into are null.

What am I missing?  These programs were all originally written for
system III but I can't think why that would matter.

If this sounds too simple for wizards, reply directly to me.

Thanks.
Mary Mallott
mm1751 at almsa-1.ARPA