+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" @(#)clock.3 5.4 (Berkeley) 6/29/91
+.\"
+.Dd June 29, 1991
+.Dt CLOCK 3
+.Os
+.Sh NAME
+.Nm clock
+.Nd determine processor time used
+.Sh SYNOPSIS
+.Fd #include <sys/types.h>
+.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 .