Like this? 

open NUL, '<', 'nul' or die $!;;
defined( $s = readline( NUL )) or die $!;;
[Died at (eval 9) line 1.

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Or 

open O, '>', 'nul' or die $!;;
defined( $s = readline( O )) or die $!;;
Filehandle O opened only for output at (eval 11) line 1.

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP PCW

In reply to Re: Generating a readline error by BrowserUk
in thread Generating a readline error by ikegami

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