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clock(3)

NAME

     clock -- determine processor time used

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <time.h>

     clock_t
     clock(void);

DESCRIPTION

     The clock() function determines the amount of processor time used since
     the invocation of the calling process, measured in CLOCKS_PER_SECs of a
     second.

RETURN VALUES

     The clock() function returns the amount of time used unless an error
     occurs, in which case the return value is -1.

SEE ALSO

     getrusage(2), clocks(7)

STANDARDS

     The clock() function conforms to ISO/IEC 9899:1990 (``ISO C90'').	How-
     ever, Version 2 of the Single UNIX Specification (``SUSv2'') requires
     CLOCKS_PER_SEC to be defined as one million.  FreeBSD does not conform to
     this requirement; changing the value would introduce binary incompatibil-
     ity and one million is still inadequate on modern processors.

FreeBSD 5.4			 June 4, 1993			   FreeBSD 5.4

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