# from Ken Williams
# on Sunday 04 February 2007 07:13 pm:
>On Feb 1, 2007, at 5:42 PM, Andreas J. Koenig wrote:
>> The offending line:
>>
>> + return $ENV{PERL_MM_USE_DEFAULT} || ( !$self->_is_interactive &&
>> eof STDIN );
>>
>> This hangs forever when the STDOUT is redirected and STDIN is not
>> redirected.
>
>Indeed.
>
>I think I've got a reasonable fix, does it look reasonable to you?
>Of course, STDIN could be something more exotic like a tied fh, and
>then I guess we'd be at the mercy of whomever tied it...
>
>I found this by looking in the perl source for the smallest wrapper
>around the PerlIOValid() macro.
>+ return $ENV{PERL_MM_USE_DEFAULT}
>+ || ( !$self->_is_interactive && !defined fileno STDIN );
From my experiment, this doesn't change the behavior. It just causes it
to hang later in _readline() instead.
return $ENV{PERL_MM_USE_DEFAULT} ||
( !$self->_is_interactive && (-t STDIN ? 1 : eof(STDIN));
I think this gives you the correct answer for _is_unattended() -- where
STDOUT is being redirected, we are unattended unless we're being fed a
set of scripted answers on STDIN.
--Eric
--
hobgoblin n 1: (folklore) a small grotesque supernatural creature that
makes trouble for human beings
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