std.zip and a large archive

[via Digitalmars-d-learn]

On Saturday, 19 July 2014 at 07:55:10 UTC, AntonSotov wrote:
> I process archive:
> ///////////////
> import std.stdio, std.zip, std.file;
>
> int main()
> {
>   auto zip = new ZipArchive(read("c:/test.zip"));
>   foreach (item; zip.directory) {
>     writeln("processing ", item.name, " ...");
>     // processing item...
>   }
>   return 0;
> }
> /////////////////
> it works well for normal archives.
> but how to process zip archive ~1GB ?
> it takes a long of RAM.

Hmm... it's unfortunate that ZipArchive doesn't take a file 
descriptor. As a workaround, you can use memory mapping:

import std.stdio, std.zip, std.file, std.mmfile;

int main()
{
   auto mmfile = new MmFile(File("c:/test.zip", "rb"));
   auto zip = new ZipArchive(mmfile[]);
   foreach (item; zip.directory) {
     writeln("processing ", item.name, " ...");
     // processing item...
   }
   return 0;
}