Hi,
atof (and hence strtod) on hexadecimal numbers results in 0.0 (errno
of 0). This may be related to an old issue where NaN isnt correctly
parsed. I believe it isnt correct behaviour:
http://www.opengroup.org/onlinepubs/000095399/functions/atof.html
I've tested it for integers in the range 0x8000000 to 0xFFFFFFFF. It
works properly on
ubuntu dapper, gcc 4.1 on i386;
debian stable, gcc 3.3 on amd64
sunos ?, gcc 3.4 on sparc
I'm using standard cygwin distribution, which uses gcc 3.4.4 (cygming
special)
Sample code:
#include "limits.h"
#include <iostream.h>
#include "errno.h"
int main()
{
cout << ULONG_MAX << endl;
cout << 0xFFFFFFFF << endl;
errno = 0;
cout << atof("0xFFFFFFFF") << endl;
cout << errno << endl;
errno = 0;
cout << strtod("0xFFFFFFFF", NULL) << endl;
cout << errno << endl;
}
Is this being fixed? I could find a mention of it before. Does anyone
know a simple workaround?
Thanks
Paul