.\" Copyright (c) 1990, 1991 The Regents of the University of California. .\" All rights reserved. .\" .\" This code is derived from software contributed to Berkeley by .\" the American National Standards Committee X3, on Information .\" Processing Systems. .\" .\" %sccs.include.redist.man% .\" .\" @(#)clock.3 5.4 (Berkeley) 06/29/91 .\" .Dd .Dt CLOCK 3 .Os .Sh NAME .Nm clock .Nd determine processor time used .Sh SYNOPSIS .Fd #include .Ft clock_t .Fn clock void .Sh DESCRIPTION The .Fn clock function determines the amount of processor time used since the invocation of the calling process, measured in .Dv CLK_TCK Ns s. .Sh RETURN VALUES The .Fn clock function returns the amount of time used unless an error occurs, in which case the return value is \-1. .Sh SEE ALSO .Xr getrusage 2 .Sh STANDARDS The .Fn clock function conforms to .St -ansiC .