Reading file as binary

[baws]

On Wednesday, 29 May 2013 at 22:03:24 UTC, baws wrote:
> Im trying to learn D, lovely language for a C++ lover. I have a 
> file Im trying to parse, but I need to read the contents as 
> binary data. I also need help understanding how read() works. 
> I'd like to read the first four bytes which identify the file 
> header, I need it to show as a sequence of bytes, how can i 
> output the first 4 bytes to show like 0xFFCF?
>
> With my code, im getting the integer values, If i use 
> cast(byte[]) on read and writefln("Reading header info: 0x%x", 
> bytesRead[0]);
>
> Ill only get the first byte 0xCF.
>
>
> import std.stdio;
> import std.file;
> import std.array;
>
> struct xsdhead{
>     int head1;
>     int head2;
>     int numTables;
> };
>
> immutable int headerInfo1 = 0xFFCF;
> immutable int headerInfo2 = 0x0002;
>
> int main(string [] args){
>     writeln("start");
>     if(args[1] == null){
>         writeln("pass a file");
>         return 0;
>     }
>     auto file = args[1];
>     writeln("Working on ", file);
>
>     auto bytesRead =  cast(byte[]) read(file, 4);
>     writefln("Reading header info: %s", bytesRead);
>     writefln("Address of caret is: 0x%X", &bytesRead);
>
>     return 0;
> }

Erhm, why isnt this compiling guys? all i did was add your 
suggestions... :/

import std.stdio;
import std.file;
import std.array;

struct xsdhead{
     int head1;
     int head2;
     int numTables;
};

immutable int headerInfo1 = 0xFFCF;
immutable int headerInfo2 = 0x0002;

int main(string [] args){
     writeln("start");
     if(!args[1]){
         writeln("pass a file");
         return 0;
     }
     auto file = args[1];
     writeln("Working on: ", file);

     auto bytesRead =  cast(byte[])read(file, 4);
     writefln("Reading header info: 0x%(%02x%)", bytesRead);

     return 0;
}