Download file via http

[Kai Meyer]

I've been trying to modify the htmlget.d example for std.socketstream 
(http://www.d-programming-language.org/phobos/std_socketstream.html) to 
be able to download a file. My code ends up looking like this at the end:

         auto outfile = new std.stream.File(destination, FileMode.Out);
         outfile.copyFrom(ss, bytes_needed);

I get bytes_needed from the Content-Length header. The I get the correct 
number of bytes from the Content-Length, bytes_needed gets the right 
value, but the resulting file isn't right. The file has the right number 
of bytes, but I appear to have an extra '0a' at the very beginning of 
the file, but if I do 'ss.getchar()', to get rid of it, I get an 
exception that there's not enough data in the stream.

Here's the output from hexdump that I'm basing my analysis from. Sorry 
if it doesn't come through 100% formatted correctly.

[kai at server _source]$ hexdump -C correct_file.exe | head
00000000  4d 5a 60 00 01 00 00 00  04 00 10 00 ff ff 00 00 
|MZ`.............|
00000010  fe 00 00 00 12 00 00 00  40 00 00 00 00 00 00 00 
|........ at .......|
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 
|................|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 60 00 00 00 
|............`...|
00000040  52 65 71 75 69 72 65 73  20 57 69 6e 33 32 20 20  |Requires 
Win32  |
00000050  20 24 16 1f 33 d2 b4 09  cd 21 b8 01 4c cd 21 00  | 
$..3....!..L.!.|
00000060  50 45 00 00 4c 01 06 00  00 00 00 00 00 00 00 00 
|PE..L...........|
00000070  00 00 00 00 e0 00 8e 81  0b 01 08 00 00 7e 28 00 
|.............~(.|
00000080  00 02 00 00 00 00 00 00  8c d7 27 00 00 20 00 00 
|..........'.. ..|
00000090  00 a0 28 00 00 00 40 00  00 10 00 00 00 02 00 00 
|..(... at .........|
[kai at server _source]$ hexdump -C downloaded_file.exe | head
00000000  0a 4d 5a 60 00 01 00 00  00 04 00 10 00 ff ff 00 
|.MZ`............|
00000010  00 fe 00 00 00 12 00 00  00 40 00 00 00 00 00 00 
|......... at ......|
00000020  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 
|................|
00000030  00 00 00 00 00 00 00 00  00 00 00 00 00 60 00 00 
|.............`..|
00000040  00 52 65 71 75 69 72 65  73 20 57 69 6e 33 32 20  |.Requires 
Win32 |
00000050  20 20 24 16 1f 33 d2 b4  09 cd 21 b8 01 4c cd 21  | 
$..3....!..L.!|
00000060  00 50 45 00 00 4c 01 06  00 00 00 00 00 00 00 00 
|.PE..L..........|
00000070  00 00 00 00 00 e0 00 8e  81 0b 01 08 00 00 7e 28 
|..............~(|
00000080  00 00 02 00 00 00 00 00  00 8c d7 27 00 00 20 00 
|...........'.. .|
00000090  00 00 a0 28 00 00 00 40  00 00 10 00 00 00 02 00 
|...(... at ........|
[kai at server _source]$ hexdump -C correct_file.exe | tail
002b5c10  80 30 84 30 88 30 8c 30  90 30 94 30 98 30 9c 30 
|.0.0.0.0.0.0.0.0|
002b5c20  a0 30 a4 30 a8 30 ac 30  b0 30 b4 30 b8 30 bc 30 
|.0.0.0.0.0.0.0.0|
002b5c30  c0 30 c4 30 c8 30 cc 30  d0 30 d4 30 d8 30 dc 30 
|.0.0.0.0.0.0.0.0|
002b5c40  f4 30 f8 30 fc 30 00 31  64 31 68 31 6c 31 70 31 
|.0.0.0.1d1h1l1p1|
002b5c50  74 31 38 37 00 00 00 00  00 00 00 00 00 00 00 00 
|t187............|
002b5c60  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 
|................|
*
002b5e00  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00 
|................|
002b5e10  00 00 00 00 00 00 00 00  00 00 00 00              |............|
002b5e1c
[kai at server _source]$ hexdump -C downloaded_file.exe | tail
002b5c10  30 80 30 84 30 88 30 8c  30 90 30 94 30 98 30 9c 
|0.0.0.0.0.0.0.0.|
002b5c20  30 a0 30 a4 30 a8 30 ac  30 b0 30 b4 30 b8 30 bc 
|0.0.0.0.0.0.0.0.|
002b5c30  30 c0 30 c4 30 c8 30 cc  30 d0 30 d4 30 d8 30 dc 
|0.0.0.0.0.0.0.0.|
002b5c40  30 f4 30 f8 30 fc 30 00  31 64 31 68 31 6c 31 70 
|0.0.0.0.1d1h1l1p|
002b5c50  31 74 31 38 37 00 00 00  00 00 00 00 00 00 00 00 
|1t187...........|
002b5c60  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 
|................|
*
002b5e00  00 00 00 00 00 00 00 00  00 00 00 00 00 02 00 00 
|................|
002b5e10  00 00 00 00 00 00 00 00  00 00 00 00              |............|