find_cmd_and_exec

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 95
      def self.find_cmd_and_exec(commands, *args) # :doc:
        commands = Array(commands)

        dirs_on_path = ENV["PATH"].to_s.split(File::PATH_SEPARATOR)
        unless (ext = RbConfig::CONFIG["EXEEXT"]).empty?
          commands = commands.map { |cmd| "#{cmd}#{ext}" }
        end

        full_path_command = nil
        found = commands.detect do |cmd|
          dirs_on_path.detect do |path|
            full_path_command = File.join(path, cmd)
            begin
              stat = File.stat(full_path_command)
            rescue SystemCallError
            else
              stat.file? && stat.executable?
            end
          end
        end

        if found
          exec full_path_command, *args
        else
          abort("Couldn't find database client: #{commands.join(', ')}. Check your $PATH and try again.")
        end
      end