Free software hex editor

I have noticed that my free software hex editor (hexxed) – which is licensed under the GNU GPL – does not really come up in any searches, so here’s another entry to boost it.

It’s a bit crude, but it does some things well (e.g., display unicode and switch endianness) and it will run anywhere you can get Java to work. And as it is free software anyone is free to make it better.

This page tells you all about how to get it and use it.

Dear MI5, why don’t you use my hex editor?

MI5 text fragmentThis is a semi-serious point!

Well, British security service MI5 helped to successfully convict three would-be terrorists Richard Dart (30) of Ealing, Imran Mahmood (22) of Northolt and Jahangir Alom (26) of Stratford by what looks like scanning through temporarily (?) cached fragments of Word documents. This is a good thing.

But they have been using an 8-bit orientated hex editor – as the picture shows. If they had used my Unicode supporting  editor, Hexxed, they could have got rid of those annoying spaces between the letters.

Missing coding

English: Programmer
English: Programmer (Photo credit: Wikipedia)

Ever been engaged in an intellectual activity where the hours whizz by much faster than you think, as you puzzle over and round the issues while feeling an intense pleasure that makes the rest of the world seem less important?  This what is called “flow” and, generally, it is what I feel when I am coding.

I am not the world’s greatest coder, to be honest I am little better than average (though doing the MSc at Birkbeck made me so much better than I used to be). The pleasure doesn’t come from having a natural skill that means I can write hundreds of lines at a single sitting: like a typical programmer, if I got 20 fully debugged lines out a day, every day, I would count that as decent performance.

But lately I haven’t done any coding at all (apart from a few lines of scripting in the office to ensure SMB mounts are automatic and such like). Instead I have read a lot of computer science papers and spent a lot of time working on a presentation I need to make and a literature review that will come after.

But I miss the coding, and I am missing it more every day.

Now, coding is also very more-ish. If you code to scratch an itch then chances are you make yourself itchy by coding. So earlier this year I wrote a Groovy/Java hex editor – Hexxed – after I wrote a Linux filesystem where I could not find a hex editor that did what I wanted to do, and so on.

So, even as I puzzle about whether I should write some code just for the sake of a mental stretch, I also wonder what I would write.

Hexxed usage options

So, you want a hex editor for your latest project and (naturally) you decide to have a look at Hexxed, the free, GPL licensed, hex editor you can download here: So what happens next?

bash-3.2$ java -jar hexxed.jar -u

usage: hexxed [options]
-b,–block use block:offset address output – default is
linear address
-be,–bigendian interpret data as big endian – default is cpu
-f,–file <arg> file to edit
-le,–littleendian interpret data as little endian – default is cpu
-o,–offset <arg> offset in file – default 0
-s,–blocksize <arg> size of block if block:offset addressing used –
default is 0x200
-u,–usage show this information
-w,–width <arg> width (in bits, 8 – 64 bits) of output data –
default is 8 bits
-x,–x <arg> width of window (default 640 pixels)
-y,–y <arg> height of window (default 480 pixels)

Subtext is, please do have a look at Hexxed. I know it’s not as fully featured as commercial or even other free hex editors, but this is just the first iteration and if you tell me it is useful and add what feature you’d like to see in it, it is quite likely that I will get on with adding it.

Update: I have now run Hexxed on Ubuntu and Debian Linux, Mac OSX and Windows XP, so it should work on anything with Java installed.

A pleasingly retro look and feel

I have done almost all my development of Hexxed on a Macbook, but have now updated the git repo on my Linux laptop and run it Hexxed on Linuxthere – some interesting differences:

  • the Linux app has a pleasingly retro look and feel to it – no anti-aliased fonts here
  • on Linux key reptitition works as expected – ie if one holds down a key the application is sent multiple key events, which is what one expects and which works well with the vi-like interface I am building
  • On Linux the first file open dialog is a really crude/retro looking box (think Windows 3.0), while subsequent file open dialogs reflect the system windows toolkit.

The screenshot is of a VMUFAT volume, it was my experience of writing that driver that gave me the itch that Hexxed is meant to scrtach – in particular I wanted a hex editor that would allow me to display 16 bit numbers in a given endian form and partition the memory space by arbitary block size (VMUs use a lot of 16 bit little endian numbers and a 512 byte block size). Hexxed does both of these things now, though it still has no editing facilities – just viewing.

As for VMUFAT itself: Sadly no one on LKML seems much interested in that – the first posting got some helpful comments, but since I posted the corrected code six or so weeks ago, nothing. Suppose I will have to start poking people with an electronic stick.

Adding vi-like functionality to Hexxed

A diagram showing the key Unix and Unix-like o...
A diagram showing the key Unix and Unix-like operating systems (Photo credit: Wikipedia)

I have decided that I will model the keyboard interface for Hexxed on vi.

I know that is not what many/any coming from outside the Unix world will expect, but then there are plenty of Hex editors out there and I want to make one that will appeal to at least one niche.

As I instinctively type “:w” in all sorts of places these days, I think there will be some other people out there who might like that sort of functionality too.