Mapping of RIDs to uid_t and gid_t

[David Collier-Brown]

Jean-Francois Micouleau wrote:
> I'm still not convince by this idea. I know several sites (like where I
> worked in a previous life) where the uid are allocated in blocks to make
> some delegations to other sysadmin.

	This block-allocation is very common at at least 
	York University and several large commercial sites,
	so groups can cooperate on generating unique userids.
	This means that the high 4 bits can be taken (although
	most people avoid setting bit 31 (:-))

	Therefor ((uid+1000) & 28bits) may cause loss of
	significant digits. **May**!  It's probabilistic...


	Are the group and machine ID's randomly distributed, or are 
	they individually counted up from 0?  I'm having a half-baked
	thought (;-))
	
--dave
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David Collier-Brown,  | Always do right. This will gratify some people
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