🚀 go-pugleaf

Followups directed to comp.lang.c.

In article <1992Aug16.164006.2345@panix.com> os2man@panix.com (Larry Salomon Jr.) writes:
>>double tmp=33433.740234;
>>printf("%f %f",tmp,floor(tmp));
>>...
>
>This shouldn't have anything to do with it, but %f is for float types.  You
>should be using %lf.

That's a common misconception.  "%f" is correct for either float or
double parameters to printf().  Floats convert to double when passed
to a variadic function (eg, printf(const char*, ...)) or to an
unprototyped function.  In fact, ANSI C doesn't define a "%lf" for
printf(), so the following could crash on a very strict compiler:
	double d = 1.2;
	printf("%lf", d);  // error, "%lf" not valid for printf()
Because its such a common error, though, compilers just ignore the 'l'.

You *must* properly use %lf or %f for *scanf(), though.

Jamshid Afshar
jamshid@emx.utexas.edu