I am trying to run multiple ruby scripts simultaneously on my mac, and I'm not having any luck. I can see the the ruby processes start up, but then they immediately stop. The script works fine as a single process, no errors. Here are some examples of things I've tried.
10.times do
system "nohup ruby program.rb \"arg1 arg2\" &"
end
10.times do
`nohup ruby program.rb \"arg1 arg2\" &`
end
10.times do
system "ruby program.rb \"arg1 arg2\""
end
Do you need to start it from ruby for any specific reason? Why don't you start it 10 times directly from bash? Like:
$ for i in
seq 1 10; do nohup ruby foo.rb \&; done
Let me know..
nohup part of the question. I guess the effect would then be the same, but of course it would be a good idea to try it out.
nohup redirects its output to a file $HOME/nohup.out, unless it is explicitly redirected. You should redirect the output of each invocation to a different file.
Also, for the safe side, I would redirect stdin to /dev/null - just in case the called program reads from stdin.
10.times do |i|
system "nohup ruby program.rb 'arg1 arg2' </dev/null >#{ENV['HOME']}/nohup#{i}.out &"
end
BTW (and off topic): Are you sure, that you want to pass arg1 arg2 as a SINGLE argument to program.rb?
system? Another possibility would be to wrap (just for testing) the whole nohup-line into a shell script and trace the execution of the shell script (with set -x).You can build a solution with fork, exec and wait of the module Process.
# start child processes
10.times { fork { exec(cmd) } }
# wait for child processes
10.times { |pid| Process.wait }
Or a bit longer to play around with (Tested with Ruby 1.8.7 on Ubuntu). Added rescue nil to suppress error when waiting.
10.times do |i|
fork do
ruby_cmd = "sleep(#{10-i});puts #{i}"
exec("ruby -e \"#{ruby_cmd}\"")
end
end
10.times { Process.wait rescue nil }
puts "Finished!"
Processclass? Like theforkmethod?