The type says nothing about whether it's scanned for pointers or not.  Remember 
that it's the caller supplying the array, the void[] type just says "pass any 
type of array in".  The function should not reallocate the array (and even if 
it did, the scanning bits are copied from the original, not determined by the 
type).

In other words, the GC cares nothing about type, it only cares what bits are 
set in the memory block.  And those bits are set on allocation, not when a cast 
is made or a parameter is passed.

And on hijacking type safety, there is no type safety when reading and writing 
a stream.  Stream data comes in or goes out as untyped data, so I think using 
void[] is actually more accurate to what is happening.

-Steve




________________________________
From: Denis <2kor...@gmail.com>
To: Discuss the phobos library for D <phobos@puremagic.com>
Sent: Mon, May 10, 2010 8:38:44 AM
Subject: Re: [phobos] UnbufferedFile, or, abstracting the File ranges

On Mon, May 10, 2010 at 4:24 PM, Steve Schveighoffer
<schvei...@yahoo.com> wrote:
> I would define only 2 i/o functions:
>
> size_t read(void[] b);
> size_t write(const(void)[] b);
>
> And then the various paraphernalia around it (close, open, etc).
>
> The reason to use void[] is because any array data type can be passed to it
> without casting (imagine you wanted to read an array of ints).
>
> Reading and writing a single byte should be discouraged with unbuffered
> streams.  This is how it is in most I/O libs.  You build your unbuffered I/O
> to abstract the OS functions, then build your buffered I/O and fancy
> functionality on top of it.
>
> -Steve
>

I think it should be byte[], not void[]. First, byte[] aren't scanned
for pointers by GC. Second, it hijacks type safety. I believe you need
an explicit cast, even if you are sure about the type of data in the
file (throw in an Endianness if you are still not convienced).
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