NAME

clock − Report CPU time used

SYNOPSIS

#include <time.h>
clock_t clock(
        void );

LIBRARY

Standard C Library (libc)

STANDARDS

Interfaces documented on this reference page conform to industry standards as follows:

clock():  XPG4, XPG4-UNIX

Refer to the standards(5) reference page for more information about industry standards and associated tags. 

DESCRIPTION

The clock() function reports the amount of processor time used by the calling process and each of its terminated child processes for which a wait function has been executed. When a child process does not wait for its children, its child-process times are not included in its times. 

RETURN VALUES

The clock() function returns the amount of processor time (in microseconds) used since the first call to clock().  To convert the time to seconds, divide it by CLOCKS_PER_SEC (which is defined to be 1,000,000 in <time.h>). If the processor time used is not available or its value cannot be represented, the clock() function returns (clock_t)-1. 

SEE ALSO

Functions: ctime(3), getrusage(2), times(3), wait(2)

Standards: standards(5)