On a 32 bit system where clocks per sec equals 1000000 this function will return the same value approximately every 72 minutes.
Get wall clock time c.
If you stipulate any particular t1 then wall clock time is within the scope of iso c.
The value returned is expressed in clock ticks which are units of time of a constant but system specific length with a relation of clocks per sec clock ticks per second.
To get the number of seconds used by the cpu you will need to divide by clocks per sec.
Returns the current time of the system as time since epoch function c documentation for clock.
Returns the processor time consumed by the program.
To calculate the actual processing time of.
To obtain cpu times use the win32 getprocesstimes function.
808 23 ms see also.
It depends on how the operating system allocates the resources for the process.
Converts a time t object to a textual representation function time.
The clock function tells how much wall clock time has passed since the crt initialization during process start.
Note that this function does not strictly conform to iso c which specifies net cpu time as the return value.
For example if the cpu is shared by other processes clock time may advance slower than wall clock.
The clock time may advance faster or slower than the actual wall clock.
The gettimeofday function returns the wall clock time elapsed since the epoch and store it in the timeval structure expressed as seconds and microseconds.
If the processor is shared by other processes the clock time may advance slower than the wall clock.
The c library function clock t clock void returns the number of clock ticks elapsed since the program was launched.
It is defined in sys time h header file and takes two arguments the first arugment is reference to the timeval structure and the second argument is a null pointer.
The epoch used as reference by clock varies between systems but it is related to the program execution generally its launch.
The 10 seconds there is wall clock time the 4 seconds isn t.
Mpj wall clock time usually refers to time intervals.
To convert the value to seconds it needs to be divided by a macro clocks per sec.
Clock time may advance faster or slower than the wall clock depending on the execution resources given to the program by the operating system.
Making a system call.
We can call the clock function at the beginning and end of the code for which we measure time subtract the values and then divide by clocks per sec the number of clock ticks per second to get processor time like following.