I am using the latest gcc with Netbeans on Windows. Why doesn't long double
work? Is the printf
specifier %lf
wrong?
Code:
#include <stdio.h>
int main(void)
{
float aboat = 32000.0;
double abet = 5.32e-5;
long double dip = 5.32e-5;
printf("%f can be written %e\n", aboat, aboat);
printf("%f can be written %e\n", abet, abet);
printf("%lf can be written %le\n", dip, dip);
return 0;
}
Output:
32000.000000 can be written 3.200000e+004
0.000053 can be written 5.320000e-005
-1950228512509697500000000000000000000000000000000000000000000000000000000000000
000000000000000000000000000000000000000000000000000000000000000000000000.000000
can be written 2.725000e+002
Press [Enter] to close the terminal ...
From the printf manpage:
l (ell) A following integer conversion corresponds to a long int or unsigned long int argument, or a following n conversion corresponds to a pointer to a long int argument, or a following c conversion corresponds to a wint_t argument, or a following s conversion corresponds to a pointer to wchar_t argument.
and
L A following a, A, e, E, f, F, g, or G conversion corresponds to a long double argument. (C99 allows %LF, but SUSv2 does not.)
So, you want %Le
, not %le
Edit: Some further investigation seems to indicate that Mingw uses the MSVC/win32 runtime(for stuff like printf) - which maps long double to double. So mixing a compiler (like gcc) that provides a native long double with a runtime that does not seems to .. be a mess.