from __future__ import * 15.8.2004

macholib does symbols now

I wrote some code last night that adds some rudimentary Mach-O symbol table support to macholib. I did this primarily because py2exe introspects dll and pyd files to see if they reference PyImport_ImportModule so that it can potentially display a warning message since the extension will be able to dynamically add dependencies to the application in a way that is undetectable without actually running the code.

>>> import macholib
>>> s = macholib.SymbolTable(macholib.MachO('pygame/display.so'))
>>> for (nlist, name) in s.undefsyms:
...   if name == '_PyImport_ImportModule':
...     print name
...     break
... 
_PyImport_ImportModule

PIL plugins for obscure image formats

I've written two read-only PIL plugins for obscure image formats over the past few years. I offered them up for PIL inclusion on image-sig, but received no response whatsoever.

Anyway, here they are:

icns:

Decoder for the Mac OS X 'icns' resource format

SoftimageImage:

Decoder for lossless Softimage PICT (.pic) files

Changing win32 icons from a Mac with Perl

The current build procedure for Talking Panda involves taking two stub applications (Mac OS X, Win2K/XP) and replacing their resources. This is extremely easy for the Mac installer, because it's just a bunch of folders. It's actually so convenient that I use the Mac application bundle to house the majority of resources that the Windows installer uses. Unfortunately, I do have to change one in-exe resource for the Win32 installer: the application's icon.

The Win32 application icons are still created "by hand" using Axialis IconWorkshop, which I highly recommend. It understands the Mac OS X icns format and does everything in a few shortcut keystrokes. Eventually I hope to write a script to generate the Windows icons on the fly with PIL, but I had a bit of trouble trying to find updated specs for the Windows XP additions to the ICO format.

I did some research into the Microsoft Portable Executable File Format, but was unable to find any portable C or Python libraries that could create a new executable using an existing one as a template. py2exe does this, but it uses a non-portable C library. Whenever this happens, I generally turn to Perl. CPAN is pretty good about having modules to read/write various file formats (the only other Perl I've used in the past few years is for reading/writing Excel spreadsheets).

Unsurprisingly, CPAN did indeed have what I needed in a module called Win32::Exe, which has a pretty painless API. And here it is, my most recent Perl monstrosity. It takes 3 arguments, the source executable, the new icon, and the destination executable. If someone wrote an equivalent Python module, I'd love to switch, but this does the job quite nicely for now.

#!/usr/bin/perl

use Win32::Exe;
use strict;
my $exe = Win32::Exe->new(shift());
$exe->update(icon => shift());
$exe->write(shift()); 

(I hate Cheetah. Please, somebody write a simple pycs-compatible blog tool that uses ReST and isn't PyDS.)