clock(3C)                                                  clock(3C)


       NAME
             clock - report CPU time used

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

       DESCRIPTION
             clock returns the amount of CPU time (in microseconds) used
             since the first call to clock in the calling process.  The
             time reported is the sum of the user and system times of the
             calling process and its terminated child processes for which
             it has executed the wait system call, the pclose function, or
             the system function.

             Dividing the value returned by clock by the constant
             CLOCKS_PER_SEC (or a million), defined in the time.h header
             file, will give the time in seconds.

             The resolution of the clock is defined by CLK_TCK in limits.h,
             and is typically 1/100 or 1/60 of a second.

       REFERENCES
             popen(3S), system(3S), times(2), wait(2)

       NOTICES
             The value returned by clock is defined in microseconds for
             compatibility with systems that have CPU clocks with much
             higher resolution.  Because of this, the value returned will
             wrap around after accumulating only 2147 seconds of CPU time
             (about 36 minutes).  If the process time used is not available
             or cannot be represented, clock returns the value (clock_t)-1.
















                           Copyright 1994 Novell, Inc.               Page 1