🚀 go-pugleaf

I was recently asked a question about printf whose answer I couldn't
determine by reading K&R2 (and alas the company doesn't have a copy of
the standard to refer to).

The "h" modifier says the corresponding argument will be printed as a
short or unsigned short.

So, given:

short s;
printf("%d", s);
printf("%hd", s);

(Assuming of course that s has been initialized at some point.)

Can these two ever be different?  I'm aware of course that the short is
widened to an int during the function call, but this preserves the
value.

(A totally non-relevant piece of information is that on at least one
platform there is never a difference between these two for any value of
s from SHRT_MIN to SHRT_MAX.  But that doesn't answer the question.)

This is the main question I'm interested, but as a followup, if these
always result in the same output, why is the 'h' modifier defined in the
first place?

Some speculations:

int i;
printf("%hd", i);
printf("%d", (short)i);

This question is stretching a bit to try to find what if anything the
'h' modifier is ever used for.  Certainly the first line would have a
different result without the 'h', but casting seems like it ought to
have the same result.


K&R2 is silent on whether "%hn" is valid as a conversion specifier.  If
so, clearly this is a case in which the 'h' is absolutely required to
get the desired behavior.

Thanks,
michael j zehr