From: Eleanor McHugh <eleanor@...>
Date: 2009-05-08T23:58:01+09:00
Subject: Re: how to find and close opened file descriptor

On 8 May 2009, at 14:55, Oliver Peng wrote:
> At first, I also try to find all IO objects and close. Here is the  
> code:
>
> ObjectSpace.each_object(IO) do |io|
>    begin
>      unless io.closed?
>        io.close
>      end
>    rescue ::Exception
>    end
> end
>
> But it doesn't work because ruby doesn't create IO object for the open
> file descriptor which are inherited from parent process.

You should probably describe how your parent process is opening these  
file descriptors as clearly it's not via objects in the IO hierarchy  
or they would be accessible in the child process. As a general rule  
though, if you have control over where and when the file descriptors  
are coming into play you can use the IO.for_fd(file_descriptor) method  
and store them in a *shudder* global variable or constant...

	OPEN_FILES = []
	...
	...
	fd = some_method_that_opens_file_and_returns_descriptor
	OPEN_FILES << IO.for_fd(fd)
	...
	...

Then in the spawned child process closing these would be as simple as:

	OPEN_FILES.each { |file| file.close }



Ellie

Eleanor McHugh
Games With Brains
http://slides.games-with-brains.net
----
raise ArgumentError unless @reality.responds_to? :reason