Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!nrl-cmf!cmcl2!brl-adm!brl-smoke!gwyn From: gwyn@brl-smoke.ARPA (Doug Gwyn ) Newsgroups: comp.unix.wizards Subject: Re: struct timeval for Sys V Rel 3.0 ? Message-ID: <7871@brl-smoke.ARPA> Date: 11 May 88 14:27:20 GMT References: <14203@brl-adm.ARPA> Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB)) Organization: Ballistic Research Lab (BRL), APG, MD. Lines: 14 In article <14203@brl-adm.ARPA> cm36+@andrew.cmu.edu (C. V. R. Murthy) writes: >gettimeofday () system call. Although Wollongongs WIN Rel 1.0 (that we have) >refers to gettimeofday (2), there is no such call on at least System V Rel 3.0. gettimeofday() is Berkeley-specific although Wollongong MIGHT have provided one in their package. >Essentialy , this requires a microsecond accurate time (namely BSD's struct >timeval). I want to know how one could get time accurate to microseconds . You can't get time like that from a normal UNIX system, even a Berkeley one. Apart from the uncertainties introduced by time-sharing scheduling, most implementations don't even maintain internal time that accurately. 100Hz clock is typical. Use time() instead.