Proper way to work with huge binary files

[Jonathan M Davis]

On Tuesday, January 24, 2012 15:53:48 C wrote:
> Hello all.
> After a quick recce on the main D site I couldn't find a how-to for large
> binary files.
> 
> Suppose I'm using an old machine with limited memory, and I want to compute
> the MD5 hash of a 4 GB file.
> Do I need to buffer the input as in C++? And how should I check for
> exceptions? Example code much appreciated.
> 
> Thank you for reading.

You'd probably just use std.stdio.File's byChunk with std.md5.MD5_CTX. 
Something like

MD5_CTX md5;
md5.start();
auto file = File(filename);

foreach(ubyte[] buffer; file.byChunk(4096))
 md5.update(buffer);

ubyte[16] result;
md5.finish(result);

I've never used std.md5 though, so I'm just going by the docs on how to use 
it.

- Jonathan M Davis