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March 21, 2013
[Issue 9776] New: Make raw write mode the default
http://d.puremagic.com/issues/show_bug.cgi?id=9776

          Summary: Make raw write mode the default
          Product: D
          Version: unspecified
         Platform: All
       OS/Version: All
           Status: NEW
         Severity: enhancement
         Priority: P2
        Component: Phobos
       AssignedTo: nobody@puremagic.com
       ReportedBy: cbkbbejeap@mailinator.com


--- Comment #0 from Nick Sabalausky <cbkbbejeap@mailinator.com> 2013-03-21 07:55:05 PDT ---
On Windows, the "write*" functions automatically convert \n to \r\n. This is
both error-prone and completely unnecessary on all versions of windows that
DMD/Phobos supports (ie, at *least* as far back as XP).

On all such versions of Windows, the command line, BATch files and code editors
all handle \n perfectly fine. If there are any obscure situations where \r\n is
still expected, they are more properly handled as-needed as special cases.

The big-prone nature of non-raw write is demonstrated in this straightforward
code:

--------------------------------------
import std.file;
import std.stdio;

void transform(string str)
{
   /+ ...perform some modification of 'str'... +/
   return str;
}

void main()
{
   auto str = cast(string) read(args[1]);
   str = transform(str);
   write(str);
}
--------------------------------------

That simple code is *wrong*:

It works correctly for all input on Unix: Output newlines match input newlines.
Always. The code never asks for newlines to be messed with, and therefore they
never are.

But on Windows the behavior is just plain weird: Unix-style newlines in the
input are silently and forcefully converted to Windows-style newlines behind
the user's back. And even worse yet, *Windows*-style newlines on the input are
converted to a bizarre "Mac9 plus Windows-style" combination of "\r\r\n" (not
only is that wrong period, but this sequence is often interpreted as two
newlines which makes it even worse). Using rawWrite fixes the problem, and
creates *no* problem.

People have been caught by that bug on various occasions, such as:
https://github.com/repeatedly/mustache-d/issues/3

See also the discussion on this matter on the D newsgroup:
http://forum.dlang.org/post/20130320103418.00005416@unknown

Various people have agreed, and so far, there hasn't been anyone arguing to
keep the current behavior.

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September 21
[Issue 9776] Make raw write mode the default
http://d.puremagic.com/issues/show_bug.cgi?id=9776


Andrej Mitrovic <andrej.mitrovich@gmail.com> changed:

          What    |Removed                     |Added
----------------------------------------------------------------------------
                CC|                            |andrej.mitrovich@gmail.com


--- Comment #1 from Andrej Mitrovic <andrej.mitrovich@gmail.com> 2013-09-21 11:20:06 PDT ---
*** Issue 11087 has been marked as a duplicate of this issue. ***

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[Issue 9776] Make raw write mode the default
http://d.puremagic.com/issues/show_bug.cgi?id=9776



--- Comment #2 from Andrej Mitrovic <andrej.mitrovich@gmail.com> 2013-09-21 11:20:33 PDT ---
Simple test-case from Issue 11087:

-----
import std.file;
import std.stdio;

void main()
{
   std.file.write("test1.txt", "a\nb");

   auto file2 = File("test2.txt", "w");
   file2.write("a\nb");
   file2.close();

   auto res1 = cast(byte[])std.file.read("test1.txt");
   auto res2 = cast(byte[])std.file.read("test2.txt");

   writeln(res1);  // writes [97, 10, 98]
   writeln(res2);  // writes [97, 13, 10, 98]
}
-----

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