• C (8/8) Jan 24 2012 Hello all.
• Justin Whear (4/14) Jan 24 2012 std.stream has a BufferedStream class which doesn't care whether the
• Jonathan M Davis (13/23) Jan 24 2012 You'd probably just use std.stdio.File's byChunk with std.md5.MD5_CTX.

C <b_avic yahoo.com> writes:

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.

Justin Whear <justin economicmodeling.com> writes:

On Tue, 24 Jan 2012 15:53:48 +0000, 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.

std.stream has a BufferedStream class which doesn't care whether the 
underlying stream is text or binary. I'd start there.

Justin

"Jonathan M Davis" <jmdavisProg gmx.com> writes:

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