From: Jeremy Bopp <jeremy@...>
Date: 2011-11-06T12:25:03+09:00
Subject: Re: help trying to create a build script

On 11/05/2011 10:01 PM, Dev Guy wrote:
> Hi I am trying to create a build script and I am running into an
> issue, apparent I have to cd into the folder before I call make
> otherwise make seem to fail.
> 
> If I was at the command like I would just type
> 
> git clone path_to_repository build/
> cd build/mozilla_firefox
> make -f client.mk
> 
> however if I try this from a ruby script make barf and fails because
> it's expecting to be called from within the foder
> build/mozilla_firefox
> 
> system "git clone path_to_repository build/"
> system "make -f build/mozilla_firefox/client.mk"
> 
> I also tried the following which doesn't do what I would expect, which
> is cd into the folder
> 
> system "git clone path_to_repository build/"
> system "cd build/mozilla_firefox"
> system "make -f client.mk"
> 
> Do anyone got idea how I can get this build script working?

My recommendation here is to generally write a shell script to do what
you want and then use the system method to run that single script.
However, you can do what you want within Ruby too:

system "git clone path_to_repository build/"
Dir.chdir("build/mozilla_firefox") do
  system "make -f client.mk"
end

The thing to keep in mind is that the system method runs a subprocess to
do the work, and a subprocess cannot modify the environment of its
parent.  The current working directory of a process is part of its
environment which is why using system in an attempt to change
directories had no effect for your script.

-Jeremy