gen/FreeBSD/clock.3

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  32 .\"     @(#)clock.3     8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/gen/clock.3,v 1.12 2007/01/09 00:27:53 imp Exp $
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  35 .Dd June 4, 1993
  36 .Dt CLOCK 3
  37 .Os
  38 .Sh NAME
  39 .Nm clock
  40 .Nd determine processor time used
  41 .Sh LIBRARY
  42 .Lb libc
  43 .Sh SYNOPSIS
  44 .In time.h
  45 .Ft clock_t
  46 .Fn clock void
  47 .Sh DESCRIPTION
  48 The
  49 .Fn clock
  50 function
  51 determines the amount of processor time used since the invocation of the
  52 calling process, measured in
  53 .Dv CLOCKS_PER_SEC Ns s
  54 of a second.
  55 .Sh RETURN VALUES
  56 The
  57 .Fn clock
  58 function returns the amount of time used unless an error occurs, in which
  59 case the return value is \-1.
  60 .Sh SEE ALSO
  61 .Xr getrusage 2 ,
  62 .Xr clocks 7
  63 .Sh STANDARDS
  64 The
  65 .Fn clock
  66 function conforms to
  67 .St -isoC
  68 and
  69 .St -susv3
  70 which requires
  71 .Dv CLOCKS_PER_SEC
  72 to be defined as one million.