Benchmark: timing 10000 iterations of pack, printf...
      pack: 21 wallclock secs (10.10 usr +  9.55 sys = 19.65 CPU) @ 508.91/s (n=10000)
    printf: 24 wallclock secs (10.90 usr +  9.72 sys = 20.62 CPU) @ 484.97/s (n=10000)

Benchmark: timing 10000 iterations of pack, printf...
      pack: 21 wallclock secs (10.03 usr +  9.75 sys = 19.78 CPU) @ 505.56/s (n=10000)
    printf: 23 wallclock secs (11.88 usr + 10.72 sys = 22.60 CPU) @ 442.48/s (n=10000)