signed vs unsigned pointer warning

[Paul Jarc]

Joe Buck <Joe.Buck@synopsys.COM> wrote:
> No, (unsigned)-1 does not turn into 255, it turns into a very large
> number.

But character 255, as a signed char, is also -1, and so will also
become the same large number.  The caller must cast char to unsigned
char to ensure that EOF is distinct.  *Only* the caller can make the
distinction reliably, since only the caller knows whether this
particular -1 is supposed to be EOF.


paul