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CLOCK(3)		   Linux Programmer's Manual		      CLOCK(3)

NAME
       clock - Determine processor time

SYNOPSIS
       #include	<time.h>

       clock_t clock(void);

DESCRIPTION
       The clock() function returns an approximation of	processor time used by
       the program.

RETURN VALUE
       The value returned is the CPU time used so far as a clock_t; to get the
       number  of  seconds  used,  divide by CLOCKS_PER_SEC.  If the processor
       time used is not	available or its  value	 cannot	 be  represented,  the
       function	returns	the value (clock_t)-1.

CONFORMING TO
       ANSI  C.	 POSIX requires	that CLOCKS_PER_SEC equals 1000000 independent
       of the actual resolution.

NOTES
       The C standard allows for arbitrary values at the start of the program;
       subtract	 the value returned from a call	to clock() at the start	of the
       program to get maximum portability.

       Note  that  the	time  can  wrap	 around.   On  a  32bit	 system	 where
       CLOCKS_PER_SEC  equals 1000000 this function will return	the same value
       approximately every 72 minutes.

       On several other	implementations, the value returned  by	 clock()  also
       includes	 the times of any children whose status	has been collected via
       wait() (or another wait-type call).  Linux does not include  the	 times
       of  waited-for  children	in the value returned by clock().  The times()
       function, which explicitly returns  (separate)  information  about  the
       caller and its children,	may be preferable.

SEE ALSO
       getrusage(2), times(2)

GNU				  2002-06-14			      CLOCK(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | CONFORMING TO | NOTES | SEE ALSO

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