printf format for unsigned __int64 on Windows

Question

I need to print a ULONGLONG value (unsigned __int64). What format should i use in printf ? I found %llu in another question but they say it is for linux only.

Thanks for your help.

Solution 1

Using Google to search for “Visual Studio printf unsigned __int64” produces this page as the first result, which says you can use the prefix I64, so the format specifier would be %I64u.

Solution 2

%llu is the standard way to print unsigned long long, it's not just for Linux, it's actually in C99. So the problem is actually to use a C99-compatible compiler, i.e, not Visual Studio.

C99 7.19.6 Formatted input/output functions

ll(ell-ell) Specifies that a following d, i, o, u, x, or X conversion specifier applies to a long long int or unsigned long long int argument; or that a following n conversion specifier applies to a pointer to along long int argument.

Solution 3

Printf has different format specifiers for unsigned long long depending on the compiler, I have seen %llu and %Lu. In general I would advice you to use std::cout and similar instead.