opensolaris man page for clock

clock(3C)						   Standard C Library Functions 						 clock(3C)

NAME
       clock - report CPU time used

SYNOPSIS
       #include <time.h>

       clock_t clock(void);

DESCRIPTION
       The clock() function 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(3C) function, the pclose(3C) function, or the system(3C) function.

RETURN VALUES
       Dividing  the  value returned by clock() by the constant CLOCKS_PER_SEC, defined in the <time.h> header, will give the time in seconds.	If
       the process time used is not available or cannot be  represented, clock returns the value (clock_t) -1.

USAGE
       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).

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       times(2), popen(3C), system(3C), wait(3C), attributes(5), standards(5)

SunOS 5.11							    24 Jul 2002 							 clock(3C)