different between unicorn / unicorn_rails

$ unicorn_rails -hUsage: unicorn_rails [ruby options] [unicorn_rails options] [rackup config file]Ruby options:  -e, --eval LINE          evaluate a LINE of code  -d, --debug              set debugging flags (set $DEBUG to true)  -w, --warn               turn warnings on for your script  -I, --include PATH       specify $LOAD_PATH (may be used more than once)  -r, --require LIBRARY    require the library, before executing your scriptunicorn_rails options:  -o, --host HOST          listen on HOST (default: 0.0.0.0)  -p, --port PORT          use PORT (default: 8080)  -E, --env RAILS_ENV      use RAILS_ENV for defaults (default: development)  -D, --daemonize          run daemonized in the background  -l {HOST:PORT|PATH},     listen on HOST:PORT or PATH      --listen             this may be specified multiple times                           (default: 0.0.0.0:8080)  -c, --config-file FILE   Unicorn-specific config file      --path PATH          Runs Rails app mounted at a specific path.                           (default: /)Common options:  -h, --help               Show this message  -v, --version            Show version

$ unicorn -hUsage: unicorn [ruby options] [unicorn options] [rackup config file]Ruby options:  -e, --eval LINE          evaluate a LINE of code  -d, --debug              set debugging flags (set $DEBUG to true)  -w, --warn               turn warnings on for your script  -I, --include PATH       specify $LOAD_PATH (may be used more than once)  -r, --require LIBRARY    require the library, before executing your scriptunicorn options:  -o, --host HOST          listen on HOST (default: 0.0.0.0)  -p, --port PORT          use PORT (default: 8080)  -E, --env RACK_ENV       use RACK_ENV for defaults (default: development)  -N                       do not load middleware implied by RACK_ENV      --no-default-middleware  -D, --daemonize          run daemonized in the background  -s, --server SERVER      this flag only exists for compatibility  -l {HOST:PORT|PATH},     listen on HOST:PORT or PATH      --listen             this may be specified multiple times                           (default: 0.0.0.0:8080)  -c, --config-file FILE   Unicorn-specific config fileCommon options:  -h, --help               Show this message  -v, --version            Show version

config/unicorn.conf.rb

# See http://unicorn.bogomips.org/Unicorn/Configurator.html for complete # documentation. -rails_env = ENV['RAILS_ENV'] || 'staging'+rails_env = ENV['RAILS_ENV'] || ENV['RACK_ENV'] || 'staging'Add a comment to this line # Use at least one worker per core if you're on a dedicated server, # more will usually help for _short_ waits on databases/caches.-worker_processes rails_env == "production" ? 4 : 1+worker_processes (rails_env == "production" ? 4 : 1)  # Since Unicorn is never exposed to outside clients, it does not need to # run on the standard HTTP port (80), there is no reason to start Unicorn