clock - Report CPU time used
Standard C Library (libc)
Interfaces documented on this reference page conform to
industry standards as follows:
clock(): XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information
about industry standards and associated tags.
The clock() function reports the amount of processor time
used by the calling process and each of its terminated
child processes for which a wait function has been executed.
When a child process does not wait for its children,
its child-process times are not included in its
The clock() function returns the amount of processor time
(in microseconds) used since the first call to clock().
To convert the time to seconds, divide it by
CLOCKS_PER_SEC (which is defined to be 1,000,000 in
<time.h>). If the processor time used is not available or
its value cannot be represented, the clock() function
Functions: ctime(3), getrusage(2), times(3), wait(2)
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