While I was messing with gdbinit three weeks ago, I added a small feature that displays the messages being sent to objc_msgSend. Usually I follow the otool or IDA dump and see what’s being sent, but that it’s not very practical! So I made a dirty hack with gdbinit so that information appears automatically into GDB window. It’s not very pretty, but gdbinit is very limited 😦. Example: gdb$ 0x00002bc5 in main () --------------------------------------------------------------------------[regs] EAX: 9FF43924 EBX: 00002B9D ECX: 9FF37B64 EDX: 00403250 o d I t S z a P c ESI: BFFFF8F4 EDI: BFFFF898 EBP: BFFFF838 ESP: BFFFF7F0 EIP: 00002BC5 CS: 0017 DS: 001F ES: 001F FS: 0000 GS: 0037 SS: 001F [001F:BFFFF7F0]----------------------------------------------------------[stack] BFFFF840 : 01 00 00 00 98 F8 FF BF - A0 F8 FF BF F4 F8 FF BF ....

I was trying to add some features to gdbinit and I needed global variables. I already knew that feature wasn’t working on Mac OS X GDB and I was puzzled why it didn’t work. Some quick tests on a Linux box couldn’t reproduce the same behaviour so something is wrong with Apple’s GDB version. I finally found how it happens ! A very simple .gdbinit to test things would be:...

While browsing around http://www.apple.com/downloads to check for any interesting software (I really like the Featured 3rd party and latest software sections) I found this well designed CD burning app, Disco (http://www.discoapp.com). I really like their website design (I have a big passion for design although I can’t design anything myself) and decided to try their app since it fits two characteristics, well designed interface and a software protection! Hurray. Open it, bang, Little Snitch warns about connection attempt and a nice registration dialogue appears....

There is a new version of original +mammon gdbinit, 7.0 (available at http://truthix.dump.cz/files/.gdbinit). GDB version used by Apple has some problems with it (doesn’t recognize global variables outside each function) so it needed some fixes to work. I have changed the colors and removed the data window display (personally I don’t think it’s useful, edit define context and remove the comment for datawin). Grab it here: gdbinit If you want to see what was changed, just diff the two versions!...

Here it is with support for Leopard and extended attributes. All calls related to extended attributes are traced and dumped to /var/log/system.log (I find it more useful than fs_usage for this specific calls). Check the .c file for options related to this. For Leopard support you need to edit the .c file and change the define. I’m still searching for a better way to detect Leopard or Tiger in XCode. Maybe a Makefile flag....