dscl

[Daniel J. Luke]

On Sep 18, 2009, at 4:46 PM, Scott Haneda wrote:
> Where does adduser/addgroup get the uid and gid to start with so it  
> does not have collisions?

The best way to answer a question like this, is to look at the source:

http://trac.macports.org/browser/trunk/base/src/port1.0/portutil.tcl

proc adduser sets the uid by calling nextuid

nextuid is from Pextlib.c:

http://trac.macports.org/browser/trunk/base/src/pextlib1.0/Pextlib.c

There you can see that nextuid is implemented by NextuidCmd, which  
starts at MIN_USABLE_UID (which is set to 500) and increments until it  
finds an unused uid. (It uses the same algorithm to find an unused gid).

--
Daniel J. Luke
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