+\subsection faq_binding_ruby Ruby Binding
+
+\subsubsection faq_binding_ruby_about What is Ruby ?
+Ruby is a dynamic, reflective, general purpose object-oriented programming language that combines syntax inspired by Perl with Smalltalk-like features.
+Ruby supports multiple programming paradigms, including functional, object oriented, imperative and reflective. It also has a dynamic type system and automatic memory management;
+it is therefore similar in varying respects to Python, Perl, Lisp, Dylan, Pike, and CLU.(see official web site <a href="http://ruby-lang.org">here</a>)
+
+\subsubsection faq_binding_ruby_simgrid Use Ruby in Simgrid
+Since v3.4 , the use of ruby in simgrid is available for the MSG Module .
+you can find almost all MSG functionalities in Ruby code , that allows you to set up your environment , manage tasks between hosts and run the simulation.
+
+\subsubsection faq_binding_ruby_example Master/Slave Ruby Application
+for each process method(master and slave in this example), you have to associate a ruby class , that should inherit from <i>MSG::Process</i> ruby class,
+ with a 'main' function that describe the behaviour of the process during the simulation.
+\li required stuff
+\verbatim
+require 'simgrid'
+include MSG
+\endverbatim
+
+\li Master code
+\verbatim
+#################################################
+# Class Master
+#################################################
+class Master < MSG::Process
+ # main : that function that will be executed when running simulation
+
+ def main(args) # args is an array containing arguments for function master
+ size = args.size
+ for i in 0..size-1
+ MSG::info("args["+String(i)+"]="+args[i])
+ end
+
+ raise "Master needs 3 arguments" if size < 3
+ numberOfTask = Integer(args[0])
+ taskComputeSize = Float(args[1])
+ taskCommunicationSize = Float(args[2])
+ slaveCount = Integer(args[3])
+
+ # Creates and sends the tasks
+ for i in 0..numberOfTask-1
+ task = Task.new("Task_"+ i.to_s, taskComputeSize , taskCommunicationSize);
+ mailbox = "slave " + (i%slaveCount).to_s
+ MSG::info("Master Sending "+ task.name + " to " + mailbox + " with Comput Size " +
+ task.compSize.to_s)
+ task.send(mailbox)
+ MSG::info("Master Done Sending " + task.name + " to " + mailbox)
+ end
+
+ # Sending Finalize MSG::Tasks
+ MSG::info("Master: All tasks have been dispatched. Let's tell everybody the computation is over.")
+ for i in 0..slaveCount-1
+ mailbox = "slave " + i.to_s
+ finalize_task = Task.new("finalize",0,0)
+ finalize_task.send(mailbox)
+ end
+ MSG::info("Master : Everything's Done")
+ end
+end
+\endverbatim
+the class MSG::Task contains methods that allows the management of the native MSG tasks.
+in master ruby code we used :
+ - <i>MSG::Task.new(task_name,compute_size,communication_size)</i> : to instanciate a new task.
+ - <i>MSG::Task.send(mailbox)</i> : to send the task via a mailbox alias.
+ - <i>MSG::Task.name</i> : to get the task's name.
+
+\li Slave code
+\verbatim
+#################################################
+# Class Slave
+#################################################
+class Slave < MSG::Process
+
+ def main(args)
+ mailbox = "slave " + args[0]
+ for i in 0..args.size-1
+ MSG::debug("args["+String(i)+"]="+args[i])
+ end
+
+ while true
+ task = Task.receive(mailbox)
+ if (task.name == "finalize")
+ break
+ end
+ task.execute
+ MSG::debug("Slave '" + mailbox + "' done executing task "+ task.name + ".")
+ end
+ MSG::info("I'm done, see you")
+ end
+end
+\endverbatim
+to receive a task , we use the method <i>MSG::Task.receive(mailbox)</i> that return a MSG:Task object (received task).
+
+\li Main chunk
+\verbatim
+if (ARGV.length == 2)
+ MSG.createEnvironment(ARGV[0])
+ MSG.deployApplication(ARGV[1])
+else
+ MSG.createEnvironment("platform.xml")
+ MSG.deployApplication("deploy.xml")
+end
+MSG.run
+puts "Simulation time : " + MSG.getClock .to_s
+MSG.exit
+\endverbatim
+- <i>MSG.createEnvironment(platform_file)</i> : set up the environment
+- <i>MSG.deployApplication(deployment_file)</i> : load the deployment file description.
+- <i>MSG.run</i> : run the simulation
+
+\subsubsection faq_binding_ruby_data Exchanging data
+ruby bindings provides two ways to exchange data between ruby processes.
+\li MSG::Task.join & MSG::Task.data \br
+
+ the MSG::Task class contains 2 methods that allows a data exchange between 2 process.
+
+ -<i>MSG::Task.join</i> : makes possible to join any kind of ruby data within a task.
+ \verbatim
+ ...
+ myTable = Array.new
+ myTable <<1<<-2<<45<<67<<87<<76<<89<<56<<78<<3<<-4<<99
+ # Creates and send Task With the Table inside
+ task = MSG::Task.new("quicksort_task",taskComputeSize, taskCommunicationSize);
+ task.join(myTable);
+ ...
+ task.send(mailbox);
+ \endverbatim
+ -<i>MSG::Task.data</i> : to access to the data contained into the task.
+ \verbatim
+ ...
+ task = MSG::Task.receive(recv_mailbox.to_s)
+ table = task.data
+ quicksort(table,0,table.size-1)
+ ...
+ \endverbatim
+you can find a complet example illustrating the use of those methods in file /example/ruby/Quicksort.rb
+
+\li inheritence
+
+ another 'object-oriented' way to do it , is to make your own 'task' class that inherit from MSG::Task ,
+ and contains data you want to deal with , the only 'tricky' thing is that "the initializer" method has no effect !
+
+ the use of some getter/setter methods would be the simple way to manage your data :)
+ \verbatim
+class PingPongTask < MSG::Task
+ # The initialize method has no effect
+ @time
+ def setTime(t)
+ @time = t
+ end
+ def getTime()
+ return @time
+ end
+end
+ \endverbatim
+ you can find an example of use in file example/ruby/PingPong.rb
+
