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Re: Can we do global bug fixes that change behavior?

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Reini Urban
July 4, 2011 19:20
Re: Can we do global bug fixes that change behavior?
Message ID:
2011/6/29 Christian Walde <>:
> On Wed, 29 Jun 2011 00:24:40 +0200, Leon Timmermans <>
> wrote:
>> On Tue, Jun 28, 2011 at 11:31 PM, Christian Walde
>> <> wrote:
>>> xdg suggested on IRC that i ask this as a separate question, so:
>>> obra:
>>> Assuming p5p reaches an agreement that magical newline-changing on
>>> Windows
>>> is a bug, would you agree to changing the behavior globally for the
>>> interpreter; or only accept it as a lexical fix when 'use v5.16' is in
>>> effect no matter what the concensus is?
>>> leont indicated that this kind of change could be applied with zero ill
>>> effects from 5.14 on, and with a possible performance regression from
>>> 5.12
>>> on.
>> It should be easy from an implementation point of view. My main
>> concern is that files written in current versions will show up
>> differently in the newer versions (carriage returns at the end of
>> lines), and that would cause some breakage.
> This problem exists currently already, since files written on Windows by
> $fh->print("\n") will contain magic \rs, which will break when read on linux
> with the expectation of only \n.

This is no convincing argument.
\r\n is no magic on windows, it is the default.
unix has d2u to get rid of this.
When you want to write to unix files or streams on windows use binmode or :raw,
instead of textmode. If you use internet protocols use :crlf.

For compatibility most internet protocols (HTTP, MIME, NNTP) use
explicitly CRLF, not LF only. Even on unix.
So you have to convince your scripts to do the right thing, not break
perl's textmode on windows.

>> Such a transition could be made easier by a generic :text. This layer
>> should probably be based on the robustness principle (e.g. it should
>> accept both LF and CRLF line-endings for input, but only output LF).
> I'm a bit confused this would come in if it wouldn't be an auto-applied
> layer no matter what OS?

Reini Urban 

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