I am new to ruby and thought it would be a great idea to rebuild a simple chat program I made in C#.
I am using Ruby 2.0.0 MRI (Matz’s Ruby Implementation).
The problem is I want to have I/O for simple server commands while the server is running. This is the server that was taken from the sample. I added the commands method that uses gets() to get input. I want this method to run as a thread in the background, but the thread is blocking the other thread.
require 'socket' # Get sockets from stdlib
server = TCPServer.open(2000) # Socket to listen on port 2000
def commands
x = 1
while x == 1
exitProgram = gets.chomp
if exitProgram == "exit" || exitProgram == "Exit"
x = 2
abort("Exiting the program.")
end
end
end
def main
Thread.start(commands)
Thread.start(server.accept)
loop { # Servers run forever
Thread.start(server.accept) do |client|
client.puts(Time.now.ctime) # Send the time to the client
client.puts "Closing the connection. Bye!"
client.close # Disconnect from the client
end
}
end
main
This is the client so far.
require 'socket' # Sockets are in standard library
hostname = 'localhost'
port = 2000
s = TCPSocket.open(hostname, port)
while line = s.gets # Read lines from the socket
puts line.chop # And print with platform line terminator
end
s.close # Close the socket when done
gets.chomp
In order to create new threads, Ruby provides ::new , ::start , and ::fork . A block must be provided with each of these methods, otherwise a ThreadError will be raised. When subclassing the Thread class, the initialize method of your subclass will be ignored by ::start and ::fork .
The Ruby interpreter handles the management of the threads and only one or two native thread are created.
Rails as a framework is thread-safe. So, the answer is yes!
Multi-threading is the most useful property of Ruby which allows concurrent programming of two or more parts of the program for maximizing the utilization of CPU. Each part of a program is called Thread. So, in other words, threads are lightweight processes within a process.
Read the documentation for Thread.new
(which is the same as Thread.start
here)
Thread.start(commands)
runs the commands
method and passes its return value to a thread (which then does nothing). It's blocking because you aren't starting any threads when gets
is called. You want
Thread.start { commands }
Here's a similar demo script that works just like you would expect
def commands
while gets.strip !~ /^exit$/i
puts "Invalid command"
end
abort "Exiting the program"
end
Thread.start { commands }
loop do
puts "Type exit:"
sleep 2
end
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With