Unicorn Configurator HttpServer OobGC PrereadInput StreamInput TeeInput Util Worker
UNICORN(1)                                                  UNICORN(1)


       unicorn - a rackup-like command to launch the Unicorn HTTP


       unicorn [-c CONFIG_FILE] [-E RACK_ENV] [-D] [RACKUP_FILE]


       A rackup(1)-like command to launch Rack applications using
       Unicorn.  It is expected to be started in your application root
       (APP_ROOT), but the "working_directory" directive may be used
       in the CONFIG_FILE.

       While unicorn takes a myriad of command-line options for
       compatibility with ruby(1) and rackup(1), it is recommended to
       stick to the few command-line options specified in the SYNOPSIS
       and use the CONFIG_FILE as much as possible.


       This defaults to "" in APP_ROOT.  It should be the
       same file used by rackup(1) and other Rack launchers, it uses
       the Rack::Builder DSL.

       Embedded command-line options are mostly parsed for
       compatibility with rackup(1) but strongly discouraged.


       -c, --config-file CONFIG_FILE
              Path to the Unicorn-specific config file.  The config
              file is implemented as a Ruby DSL, so Ruby code may
              executed.  See the RDoc/ri for the Unicorn::Configurator
              class for the full list of directives available from the
              DSL.  Using an absolute path for for CONFIG_FILE is
              recommended as it makes multiple instances of Unicorn
              easily distinguishable when viewing ps(1) output.

       -D, --daemonize
              Run daemonized in the background.  The process is
              detached from the controlling terminal and stdin is
              redirected to "/dev/null".  Unlike many common UNIX
              daemons, we do not chdir to "/" upon daemonization to
              allow more control over the startup/upgrade process.
              Unless specified in the CONFIG_FILE, stderr and stdout
              will also be redirected to "/dev/null".

       -E, --env RACK_ENV
              Run under the given RACK_ENV.  See the RACK ENVIRONMENT
              section for more details.

       -l, --listen ADDRESS
              Listens on a given ADDRESS.  ADDRESS may be in the form
              of HOST:PORT or PATH, HOST:PORT is taken to mean a TCP
              socket and PATH is meant to be a path to a UNIX domain
              socket.  Defaults to "" (all addresses on
              TCP port 8080) For production deployments, specifying
              the "listen" directive in CONFIG_FILE is recommended as
              it allows fine-tuning of socket options.

       -N, --no-default-middleware
              Disables loading middleware implied by RACK_ENV.  This
              bypasses the configuration documented in the RACK
              ENVIRONMENT section, but still allows RACK_ENV to be
              used for application/framework-specific purposes.


       -o, --host HOST
              Listen on a TCP socket belonging to HOST, default is
              "" (all addresses).  If specified multiple times
              on the command-line, only the last-specified value takes
              effect.  This option only exists for compatibility with
              the rackup(1) command, use of "-l"/"--listen" switch is
              recommended instead.

       -p, --port PORT
              Listen on the specified TCP PORT, default is 8080.  If
              specified multiple times on the command-line, only the
              last-specified value takes effect.  This option only
              exists for compatibility with the rackup(1) command, use
              of "-l"/"--listen" switch is recommended instead.

       -s, --server SERVER
              No-op, this exists only for compatibility with


       -e, --eval LINE
              Evaluate a LINE of Ruby code.  This evaluation happens
              immediately as the command-line is being parsed.

       -d, --debug
              Turn on debug mode, the $DEBUG variable is set to true.

       -w, --warn
              Turn on verbose warnings, the $VERBOSE variable is set
              to true.

       -I, --include PATH
              specify $LOAD_PATH.  PATH will be prepended to
              $LOAD_PATH.  The ':' character may be used to delimit
              multiple directories.  This directive may be used more
              than once.  Modifications to $LOAD_PATH take place
              immediately and in the order they were specified on the

       -r, --require LIBRARY
              require a specified LIBRARY before executing the
              application.  The "require" statement will be executed
              immediately and in the order they were specified on the


       The following UNIX signals may be sent to the master process:

       • HUP - reload config file, app, and gracefully restart all

       • INT/TERM - quick shutdown, kills all workers immediately

       • QUIT - graceful shutdown, waits for workers to finish their
         current request before finishing.

       • USR1 - reopen all logs owned by the master and all workers
         See Unicorn::Util.reopen_logs for what is considered a log.

       • USR2 - reexecute the running binary.  A separate QUIT should
         be sent to the original process once the child is verified to
         be up and running.

       • WINCH - gracefully stops workers but keep the master running.
         This will only work for daemonized processes.

       • TTIN - increment the number of worker processes by one

       • TTOU - decrement the number of worker processes by one

       See the SIGNALS (
       document for full description of all signals used by Unicorn.


       Accepted values of RACK_ENV and the middleware they
       automatically load (outside of RACKUP_FILE) are exactly as
       those in rackup(1):

       • development - loads Rack::CommonLogger, Rack::ShowExceptions,
                       Rack::Lint middleware

       • deployment - loads Rack::CommonLogger middleware

       • none - loads no middleware at all, relying entirely on

       All unrecognized values for RACK_ENV are assumed to be "none".
       Production deployments are strongly encouraged to use
       "deployment" or "none" for maximum performance.

       As of Unicorn 0.94.0, RACK_ENV is exported as a process-wide
       environment variable as well.  While not current a part of the
       Rack specification as of Rack 1.0.1, this has become a de facto
       standard in the Rack world.

       Note the Rack::ContentLength and Rack::Chunked middlewares are
       also loaded by "deployment" and "development", but no other
       values of RACK_ENV.  If needed, they must be individually
       specified in the RACKUP_FILE, some frameworks do not require


       The RACK_ENV variable is set by the aforementioned -E switch.
       All application or library-specific environment variables (e.g.
       TMPDIR) may always be set in the Unicorn CONFIG_FILE in
       addition to the spawning shell.  When transparently upgrading
       Unicorn, all environment variables set in the old master
       process are inherited by the new master process.  Unicorn only
       uses (and will overwrite) the UNICORN_FD environment variable
       internally when doing transparent upgrades.

       UNICORN_FD is a comma-delimited list of one or more file
       descriptors used to implement USR2 upgrades.  Init systems may
       bind listen sockets itself and spawn unicorn with UNICORN_FD
       set to the file descriptor numbers of the listen socket(s).

       As of unicorn 5.0, LISTEN_PID and LISTEN_FDS are used for
       socket activation as documented in the sd_listen_fds(3)
       manpage.  Users relying on this feature do not need to specify
       a listen socket in the unicorn config file.


       • Rack::Builder ri/RDoc

       • Unicorn::Configurator ri/RDoc

       • unicorn RDoc ⟨⟩

       • Rack RDoc ⟨⟩

       • Rackup HowTo


       The Unicorn Community <>.

Unicorn User Manual       September 15, 2009                UNICORN(1)

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source code: git clone
	torsocks git clone http://ou63pmih66umazou.onion/unicorn.git