From: Robert Klemme <shortcutter@...>
Date: 2009-05-20T15:14:22+09:00
Subject: Re: I want to redirect stderr to StringIO.

2009/5/20 Eric Hodel <drbrain@segment7.net>:
> On May 19, 2009, at 21:30, ErMaker wrote:
>
>>>> IO.new(2).reopen(StringIO.new)
>>
>> TypeError: can't convert StringIO into String
>>       from (irb):1:in `reopen'
>>       from (irb):1
>>>>
>>>> IO.new(2).reopen(IO.new(1))
>>
>> => #<IO:0x2a81630>
>>
>> StringIO also do as IO, but IO#reopen fails.
>>
>> I want to redirect stderr to StringIO, but it doesn't work.
>
> Always use reopen as a last resort.
>
> http://blog.segment7.net/articles/2006/08/17/stdout-vs-stdout

I am not sure I agree.  Actually, if you want the redirection to be
permanent for sub processes you have to use $stdout.reopen.  And this
is not a "last resort" but the proper solution.

Btw, in 1.8 there is also $defout - I believe _that- is the stream
used by Kernel#puts and the like in those versions:

08:13:00 ~$ ruby -r stringio -e 'puts 1; $defout=StringIO.new; puts 2'
1
-e:1: warning: $defout is obsolete; use $stdout instead
08:13:30 ~$

Cheers

robert


-- 
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