Directory changes made through system calls like system "cd directory" do not affect the current Ruby process. Each system call runs
in a separate subprocess with its own environment. When the subprocess exits, any directory changes are lost, and the parent Ruby process remains in
its original directory.
This leads to unexpected behavior where subsequent system calls or file operations don’t run in the intended directory. For example, if you run
system "cd my_app" followed by system "rails server", the Rails server will start in the original directory, not in the
my_app directory.
Ruby provides the Dir.chdir method specifically for changing the working directory within the current process. This method actually
changes the directory for the Ruby process itself, making it the correct approach for directory navigation in Ruby scripts.
What is the potential impact?
Using system calls for directory changes can cause scripts to fail silently or behave unexpectedly. Commands may run in the wrong directory,
leading to file not found errors, incorrect file operations, or applications starting in unexpected locations. This can result in deployment failures,
data corruption, or security issues if files are created or modified in unintended directories.
