Thanks! I didn't experiment with gmtime_r() since it goes in the other direction (UnixTime -> civil time). I wouldn't expect timegm() or gmtime_r() to depend

Thanks! I didn't experiment with gmtime_r() since it goes in the other direction (UnixTime -> civil time). I wouldn't expect timegm() or gmtime_r() to depend on current timezone, since both are hard-coded to use UTC. I never did figure out why the macOS version is performing mutex locks on global data.