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CLOCK(3)                                BSD Library Functions Manual                                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'').  However, 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 incompatibility and one million
     is still inadequate on modern processors.

BSD                                             June 4, 1993                                             BSD