backtick vs system in ruby

Question

Base on all my readings on the web the difference between backtick and system is what is returned . backtick returns STDOUT while system returns true or false.

And I was told that both of them use subshell to perform the operation.

However I am noticing another difference.

output = system('aaa')
puts "output is: #{output}"

output = `aaa`
puts "output is: #{output}"

Result of above code is

$ ruby test.rb
output is: 
lab.rb:4:in ``': No such file or directory - aaa (Errno::ENOENT) from test.rb:4:in `<main>'

So it seems in the case of backtick the exceptions are raised to the main program. Operation system swallows the exception and the main program never sees the exception.

I'm using ruby 1.9.3 .

Is my analysis right ?

UPDATE: Got the answer. It's here https://gist.github.com/3730986 .

Answer 1

Copying the answer from the edited question body in order to remove this question from the "Unanswered" filter:

Got the answer. It's here https://gist.github.com/3730986 .

~ answer per nodejs99