clock(3C)                                                         clock(3C)

NAME
     clock - report CPU time used

SYNOPSIS
     #include <time.h>

     clockt clock(void);

DESCRIPTION
     clock() returns the 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 CLOCKSPERSEC,
     defined in the time.h header file, will give the time in seconds.

     The resolution of the clock unit is hardware dependent.

NOTES
     The value returned by clock() is defined in microseconds for compati-
     bility with systems that have CPU clocks with much higher resolution.
     Because of this, the value returned will wrap around after accumulat-
     ing 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 (clockt)-1.

SEE ALSO
     times(2), wait(2), popen(3S), system(3S).

























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