From: Dan Zwell <dzwell@...>
Date: 2007-07-22T18:30:23+09:00
Subject: Re: IO.popen - continuous output

Sebastian Hungerecker wrote:
> Dan Zwell wrote:
> 
>> file1:
>> #!/usr/bin/env ruby
>> 5.times {puts "hi"; sleep 0.5}
>>
>> file2:
>> #!/usr/bin/env ruby
>> IO.popen("./file1").each_line { |line| puts line }
>>
>> When running file2 (which should stream the output from file1), the
>> output is not streamed, but instead saved up until "file1" finishes
>> running and then dumped.
> 
> That seems to be a buffering issue. If you set STDOUT.sync to true in file1,
> it will work as expected.
> 
> 

Thanks, that's good to know. Having this behavior unexplained made me a 
bit nervous about using IO.popen.