From: "Sandor Szücs" <sandor.szuecs@...>
Date: 2008-07-22T04:24:38+09:00
Subject: Re: How to invoke an external program and get anything the pgm returns back


On 21.07.2008, at 20:35, Victor Reyes wrote:

> I tried:
> Ruby script segment:
>       rc = `/usr/local/bin/script_name`
>
> I also tried in the Ruby caller script:
>      system("/usr/local/bin/script_name")
>
> KSH:
> exit 99

Ask $? to get the information.
$?.exitstatus

> But *rc* does not have anything of value. It has either *true* or  
> *false*.


irb> res = `ls file_not_exists`
ls: file_not_exists: No such file or directory
=> ""
irb> $?.exitstatus
=> 1

According to ri page Kernel.system also sets $?


$ qri Kernel.system
---------------------------------------------------------- Kernel#system
      system(cmd [, arg, ...])    => true or false
------------------------------------------------------------------------
      Executes cmd in a subshell, returning true if the command was
      found and ran successfully, false otherwise. An error status is
      available in $?. The arguments are processed in the same way as
      for Kernel::exec.

hth. regards, Sandor Szücs
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