Re: the time a program runs

Octavian Rasnita wrote: 
Hi,

I have tried to find out the time a perl program runs, and I have used:

#at the start of the program:
my $begin = (times)[0];
my $begin_t = time();

... The program follows

# at the end of the program:
my $end = (times)[0] - $begin;
my $end_t = time() - $begin_t;
print "end: $end\nEnd_t: $end_t\n";

After running the program, it prints:

end: 4.953
End_t: 19

Why does this difference appear?


The program is a very short one, for testing the speed of Storable module.


Try this:

The global var $^T stores the time of execution start.
So at the end you want:

print (time() - $^T) , " seconds to complete\n";

However, if you want more accuracy then you might consider Time::HiRes or better yet Benchmark. Benchmark is a very useful tool.
.

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