Bug #9688
closed
Ruby's child process inherits parent's sockets (mswin)
Description
When Ruby application creates child process, sockets are inherited from the parent process.
This causes severe troubles.
In my situation, I have some web services using WEBrick and Sinatra. They invoke child process as a batch file using kernel.system method. And in the batch file I launch some long running applications by 'start'.
If these type of long running applications stay in running state, I never restart the services because the children grab server sockets while running. What is worse that Windows never report EADDRINUSE so I have no clue to judge its condition. Indeed 'netstat /b' reports the port is occupied by System not the child app.
Below is the reproduction script.
require 'socket'
require 'timeout'
exit unless RUBY_PLATFORM =~ /mswin/
BAT = "#{ENV['TMP']}#{File::SEPARATOR}test_inheritsock.bat"
File.open(BAT, 'w') do |fout|
fout.puts 'start ruby -e "sleep(10)"'
end
port = nil
TCPServer.open(0) do |gs|
port = gs.addr[1]
system(BAT)
end
File.delete BAT
gs = TCPServer.open(port)
running = true
client = false
begin
timeout(20) do
while running
Thread.start do
s = gs.accept
s.gets
s.close
running = false
end
unless client
client = true
Thread.start do
TCPSocket.open('localhost', port) do |sock|
sock.puts('')
end
end
else
sleep(1)
end
end
end
puts 'no problem'
rescue Timeout::Error
puts 'failed'
end
gs.close
The second opend TCPServer can not receive a connection request.
Unak already made no inheritance patch (https://gist.github.com/unak/9825743) and I tested it with Windowds7(x86) and Windows8.1(x64) and in both environments the above script runs completely.
So I wonder if the patch is applied to the trunk.
Thanks in advance.
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