measure executing time of command line calls

Question

I am writing a Ruby 1.9.2 script for evaluating the execution times of different external command line calls.

I used the ruby Process.system method to execute the command line calls and tried to capture the executing time as follows:

start = Time.now
system("./script1", "argX")

puts "Duration: #{Time.now - start} seconds"

Now I have the problem that the duration doesn't reflect the execution time of the external process but the execution time of the "system" call.

Any idea how I can measure the execution time of the external process?

Answer 1

Okay. If I understand what you are trying to do, you want to time how long the "./script1" call takes to run?

One thing you might want to do is to use the benchmark library (it's standard).

require 'benchmark'

Benchmark.bm (7) do |x|
  x.report ("script1:") {system("./script1", "argX")}
end

That will generate a report with user and system times, which may be what you want.