I would like to change network, but only for newly started process.
My idea is to modify somehow /proc
filesystem for newly created process. How to do it in linux?
Example code in ruby
script.rb
conn = Tcp.dial('123.123.123.4', 3306)
and my wrapper around process starting:
p = Process.new('script.rb')
# I would like to somehow cheat a proc system
# so process during connection to 123.(...) connects really to localhost
# a bit like
# sudo iptables -t nat -A OUTPUT -p all -d 123.123.123.4 -j DNAT --to-destination 127.0.0.1
# but for process
p.network(from: '123.123.123.4', to: :localhost)
p.start