Location of in.h in SVR4

[Lyndon Nerenberg]

Would someone who has access to a machine running SVR4 please let
me know what directory in.h is located in? Thanks.

-- 
     Lyndon Nerenberg  VE6BBM / Computing Services / Athabasca University
         {alberta,cbmvax,mips}!atha!lyndon || lyndon at cs.athabascau.ca
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