From: Corey Jewett <ml@...>
Date: 2007-07-15T13:23:13+09:00
Subject: Re: Calling a Perl script from Ruby


On Jul 14, 2007, at 9:12 PM, James Edward Gray II wrote:

> On Jul 14, 2007, at 9:44 PM, M. Edward (Ed) Borasky wrote:
>
>> Dave Coleman wrote:
>>> Tim Hunter wrote:
>>>> Check out the system() method.
>>> looks like system only returns true or false if the system call  
>>> executes
>>> successfully. What if you want to evaluate what's returned from that
>>> perl script?
>>>
>> IIRC "system" returns the (implementation-dependent) numerical return
>> code of the call, where by tradition "0" is success and non-zero  
>> is an
>> application-dependent error number. If Ruby is returning "true" on
>> success and "false" on failure, that's different from what many
>> environments do.
>
> It does, but you can get the exit code:
>
> system("date")  # => true
> $?.to_i         # => 0
> # >> Sat Jul 14 23:11:49 CDT 2007

There is also Kernel.`` which will return stdout. If you're looking  
for something more powerful still look at popen, Open3, or (best of  
all ;D) the Open4 gem.

Corey