Os.date() returns nil above an unknown, arbitrary number

[Auhrii]

Hello, I’m using os.date("!*t",os.time()) to set my game’s time of day. Imagine my surprise when I go to speed up the day/night cycle by cheating and multiplying os.time by 50, only to find os.date returning nil!

I was curious, so I punched this into the command line:

print(os.date("!*t",8451712348))

Wouldn’t you know it, it spat out a function. That time stamp is 218 years in the future. So far so good. So I stuck a 1 on the front of that number. 18451712348. Still works. Okay, how about 118451712348- no.

It works above the maximum unsigned 32-bit integer (4,294,967,295), but seems to halt and catch fire somewhere in between 18,451,712,348 and 118,451,712,348. Why is this? It seems arbitrary.

I tested the same using the live demo on the Lua website, and it keeps spitting out valid results even at os.time()*5000000.

Lua live demo screenshot

[buildthomas]

Recent post related to this:

Os.date returning nil

I just checked and the issue here is that the resulting date value you’ve created is past the year 3000 (see here for calculation: Rink ). On Windows at least, dates past 3000 will return an error, so we return nil in this case. I agree with @ee0w’s suggestion, but it’s worth noting that not all platforms will necessarily return nil, so don’t rely on it returning nil. Year 2038 problem doesn’t really apply here, as we don’t use 32-bit timestamps. The year 3000 problem though, we will have to s…

You are probably not seeing it on the Lua live demo because I’m assuming its run off a Linux back-end and not Windows. (that, and/or Roblox might be using the underlying system in a different way to get the date than stock Lua does)

[Auhrii]

Thanks - neither forum search nor the “similar topics” showed that. Good to know - will bear that in mind in future.