What algorithm did Windows XP use to choose your initial user picture?

	What algorithm did Windows XP use to choose your initial user picture?(devblogs.microsoft.com)
	352 points by soheilpro 1 day ago \| 176 comments
	tl;dr: Windows XP picked your initial user picture using reservoir sampling (k=1) over the Default Pictures directory, seeded by GetTickCount() via RtlRandomEx. This one-pass approach avoids a second file-system enumeration and handles directory changes mid-iteration gracefully. A safety cap stops sampling after 100 files to prevent pathological slowdowns.
	HN Discussion: ↑Admiration for Raymond Chen's Windows internals storytelling and longevity ↑Reflection on how modern developers would take a simpler, less elegant approach under time pressure ↑Appreciation for the thoughtful optimization mindset of past developers ↓Questioning whether the single-pass optimization actually matters given filesystem caching •Observation about the conceptual gap between human and computer randomness/selection