Provided by: rerun_0.13.1-3_all 
NAME
rerun - run programs and restarts them on filesystem changes
DESCRIPTION
Rerun launches your program, then watches the filesystem. If a relevant file changes, then
it restarts your program.
Rerun works for both long-running processes (e.g. apps) and short-running ones (e.g.
tests). It’s basically a no-frills command-line alternative to Guard, Shotgun, Autotest,
etc. that doesn’t require config files and works on any command, not just Ruby programs.
Rerun’s advantage is its simple design. Since it uses exec and the standard Unix SIGINT
and SIGKILL signals, you’re sure the restarted app is really acting just like it was when
you ran it from the command line the first time.
By default it watches files ending in:
rb,js,coffee,css,scss,sass,erb,html,haml,ru,yml,slim,md,feature,c,h. Use the --pattern
option if you want to change this.
As of version 0.7.0, we use the Listen gem, which tries to use your OS’s built-in
facilities for monitoring the filesystem, so CPU use is very light.
UPDATE: Now Rerun does work on Windows. Caveats: * not well-tested * after running, it may
continue to slurp up some of your console input, so run it in a separate window, and/or
use --background to disable on-the-fly commands, and/or press q to quit instead of CTRL-C
* you may need to install the wdm gem manually: gem install wdm * You may see this
persistent INFO error message; to remove it, use`--no-notify`: * INFO: Could not find
files for the given pattern(s)
USAGE
rerun [options] [--] cmd
For example, if you’re running a Sinatra app whose main file is app.rb:
rerun ruby app.rb
If the first part of the command is a .rb filename, then ruby is optional, so the above
can also be accomplished like this:
rerun app.rb
Rails doesn’t automatically notice all config file changes, so you can force it to restart
when you change a config file like this:
rerun --dir config rails s
Or if you’re using Thin to run a Rack app that’s configured in config.ru but you want it
on port 4000 and in debug mode, and only want to watch the app and web subdirectories:
rerun --dir app,web -- thin start --debug --port=4000 -R config.ru
The -- is to separate rerun options from cmd options. You can also use a quoted string for
the command, e.g.
rerun --dir app "thin start --debug --port=4000 -R config.ru"
Rackup can also be used to launch a Rack server, so let’s try that:
rerun -- rackup --port 4000 config.ru
Want to mimic [autotest](https://github.com/grosser/autotest)? Try
rerun -x rake
or
rerun -cx rspec
And if you’re using [Spork](https://github.com/sporkrb/spork) with Rails, you need to
[restart your spork server](https://github.com/sporkrb/spork/issues/201) whenever certain
Rails environment files change, so why not put this in your Rakefile...
desc "run spork (via rerun)"
task :spork do
sh "rerun --pattern '{Gemfile,Gemfile.lock,spec/spec_helper.rb,.rspec,spec/factories/**,config/environment.rb,config/environments/test.rb,config/initializers/*.rb,lib/**/*.rb}' -- spork"
end
and start using rake spork to launch your spork server?
(If you’re using Guard instead of Rerun, check out
[guard-spork](https://github.com/guard/guard-spork) for a similar solution.)
How about regenerating your HTML files after every change to your
[Erector](http://erector.rubyforge.org) widgets?
rerun -x erector --to-html my_site.rb
Use Heroku Cedar? rerun is now compatible with foreman. Run all your Procfile processes
locally and restart them all when necessary.
rerun foreman start
OPTIONS
These options can be specified on the command line and/or inside a .rerun config file (see
below).
--dir directory (or directories) to watch (default = "."). Separate multiple paths with
',' and/or use multiple -d options.
--pattern glob to match inside directory. This uses the Ruby Dir glob style — see
http://www.ruby-doc.org/core/classes/Dir.html#M002322 for details. By default it watches
files ending in: rb,js,coffee,css,scss,sass,erb,html,haml,ru,yml,slim,md,feature,c,h. On
top of this, it also ignores dotfiles, .tmp files, and some other files and directories
(like .git and log). Run rerun --help to see the actual list.
--ignore pattern file glob to ignore (can be set many times). To ignore a directory, you
must append '/' e.g. --ignore 'coverage/'.
*On top of --pattern and --ignore, we ignore any changes to files and dirs starting with a dot.*
--signal (or -s) use specified signal(s) (instead of the default TERM,INT,KILL) to
terminate the previous process. You can use a comma-delimited list if you want to try a
signal, wait up to 5 seconds for the process to die, then try again with a different
signal, and so on. This may be useful for forcing the respective process to terminate as
quickly as possible. (--signal KILL is the equivalent of kill -9)
--wait sec (or -w) after asking the process to terminate, wait this long (in
seconds) before either aborting, or trying the next signal in series. Default: 2 sec
--restart (or -r) expect process to restart itself, using signal HUP by default (e.g. -r
-s INT will send a INT and then resume watching for changes)
--exit (or -x) expect the program to exit. With this option, rerun checks the return
value; without it, rerun checks that the launched process is still running.
--clear (or -c) clear the screen before each run
--background (or -b) disable on-the-fly commands, allowing the process to be backgrounded
--notify NOTIFIER use growl or osx or notify-send for notifications (see below)
--no-notify disable notifications
--name set the app name (for display)
--force-polling use polling instead of a native filesystem scan (useful for Vagrant)
--quiet silences most messages
--verbose enables even more messages (unless you also specified --quiet, which overrides
--verbose)
Also --version and --help, naturally.
CONFIG FILE
If the current directory contains a file named .rerun, it will be parsed with the same
rules as command-line arguments. Newlines are the same as any other whitespace, so you can
stack options vertically, like this:
--quiet
--pattern **/*.{rb,js,scss,sass,html,md}
Options specified on the command line will override those in the config file. You can
negate boolean options with --no-, so for example, with the above config file, to
re-enable logging, you could say:
rerun --no-quiet rackup
If you’re not sure what options are being overwritten, use --verbose and rerun will show
you the final result of the parsing.
NOTIFICATIONS
If you have growlnotify available on the PATH, it sends notifications to growl in addition
to the console.
If you have terminal-notifier, it sends notifications to the OS X notification center in
addition to the console.
If you have notify-send, it sends notifications to Freedesktop-compatible desktops in
addition to the console.
If you have more than one available notification program, Rerun will pick one, or you can
choose between them using --notify growl, --notify osx, --notify notify-send, etc.
If you have a notifier installed but don’t want rerun to use it, set the --no-notify
option.
Download [growlnotify here](http://growl.info/downloads.php#generaldownloads) now that
Growl has moved to the App Store.
Install [terminal-notifier](https://github.com/julienXX/terminal-notifier) using gem
install terminal-notifier. (You may have to put it in your system gemset and/or use sudo
too.) Using Homebrew to install terminal-notifier is not recommended.
On Debian/Ubuntu, notify-send is availble in the libnotify-bin package. On other GNU/Linux
systems, it might be in a package with a different name.
ON-THE-FLY COMMANDS
While the app is (re)running, you can make things happen by pressing keys:
• r — restart (as if a file had changed)
• f — force restart (stop and start)
• c — clear the screen
• x or q — exit (just like control-C)
• p — pause/unpause filesystem watching
If you’re backgrounding or using Pry or a debugger, you might not want these keys to be
trapped, so use the --background option.
SIGNALS
The current algorithm for killing the process is:
• send [SIGTERM](http://en.wikipedia.org/wiki/SIGTERM) (or the value of the --signal
option)
• if that doesn’t work after 2 seconds, send SIGINT (aka control-C)
• if that doesn’t work after 2 more seconds, send SIGKILL (aka kill -9)
This seems like the most gentle and unixy way of doing things, but it does mean that if
your program ignores SIGTERM, it takes an extra 2 to 4 seconds to restart.
If you want to use your own series of signals, use the --signal option. If you want to
change the delay before attempting the next signal, use the --wait option.
VAGRANT AND VIRTUALBOX
If running inside a shared directory using Vagrant and VirtualBox, you must pass the
--force-polling option. You may also have to pass some extra --ignore options too;
otherwise each scan can take 10 or more seconds on directories with a large number of
files or subdirectories underneath it.
TROUBLESHOOTING
Vagrant
Rerun will not pick up changes made to shared folders. This means that the common method
of using Vagrant for an execution environment and using the /vagrant shared folder for
source code will not work.
Instead, use [shotgun](https://rubygems.org/gems/shotgun).
zsh
If you are using zsh as your shell, and you are specifying your --pattern as */.rb, you
may face this error
Errno::EACCES: Permission denied - <filename>
This is because */.rb gets expanded into the command by zsh instead of passing it through
to rerun. The solution is to simply quote ('' or "") the pattern. i.e
rerun -p **/*.rb rake test
becomes
rerun -p "**/*.rb" rake test
2022-12-23 RERUN(1)