Contents

require 'io/wait'

ENV['X'] = 'ex'

# open a pipe to `sub.rb` for reading and writing
fp = IO.popen("ruby #{File.dirname(__FILE__)}/sub.rb", 'r+')

# read the initial dump from it
sub_output_1 = ""
# we need to wait until it's sent data
sleep 1 while (not fp.ready?)
# then read into `sub_output_1` while it's still has data
while fp.ready?
  # i don't know if i need to read in chunks of 1 or what but that seemed
  # like a safe choice. there is a also a `read_nonblocking` call that
  # might be useful instead but looks kinda complicated
  sub_output_1 += fp.read(1)
end
# ok, there is no more output waiting
# dump what we have
puts "*** SUB OUTPUT 1 ***"
puts sub_output_1

# this means the pipe is read for input
# we now have control back and sub is blocked waiting on our write
# change an ENV var now
ENV['Y'] = 'why'
puts "WRITING...."
fp.puts "hey there!"
puts "WRITTEN."

# that should get sub un-blocked
# now repeat the process above to see what it says
sub_output_2 = ""
sleep 1 while (not fp.ready?)
while fp.ready? && (not fp.eof?)
  sub_output_2 += fp.read(1)
end
puts "*** SUB OUTPUT 2 ***"
puts sub_output_2
# doesn't look like it gets the ENV update

# be a good samaritan
fp.close

Version data entries

4 entries across 4 versions & 1 rubygems

Version	Path
nrser-rash-0.2.3	dev/scratch/inheriting_env/main.rb
nrser-rash-0.2.2	dev/scratch/inheriting_env/main.rb
nrser-rash-0.2.1	dev/scratch/inheriting_env/main.rb
nrser-rash-0.2.0	dev/scratch/inheriting_env/main.rb