Benchmark: timing 1500000 iterations of sprintf, unpack...
   sprintf:  0 wallclock secs ( 0.17 usr +  0.00 sys =  0.17 CPU) @ 8823529.41/s (n=1500000)
            (warning: too few iterations for a reliable count)
    unpack: 10 wallclock secs ( 9.87 usr +  0.01 sys =  9.88 CPU) @ 151821.86/s (n=1500000)