Preprocessor macro expanding to a string
#include <SYS/TYPES.H>
__64_format
This macro expands to a format string qualifier that specifies printf or scanf arguments for __s64 or __u64 types. Because different architectures have different definitions for these types, an extra definition for the qualifier is needed.
__u64 variable = 3;
_printf("%"__64_format"u\n", variable);