2 ms·

Ah, so that's where it's coming from! I initially suspected Plan 9...

• GauntletWizard 5y ago
  As another comment noted, Perforce used this syntax too - Which is probably where Blaze got it from. I can't speak to earlier examples, but it's "obvious" enough that I would not be surprised if someone found one. I often think that a substantial portion of my job is software archaeology...