How do I edit system files from a liveCD?

[cat_pushing_a_watermelon]

I installed OS X 10.5.7 on an older Dell that I had sitting around.

 

While trying to add a custom display resolution, something went wrong. I added 2 lines of code to a system file, and rebooted. Exactly how stupid my mistake here was isn't really important.

 

After it gets through the BIOS, the bootloader immediately attempts to change the resolution to the custom resolution I edited. For whatever reason, this doesn't work and causes it to crash. There is absolutely no opportunity to do anything at all before it crashes and reboots.

 

All I need to do is remove those 2 lines of code. How the do I do it? I tried booting it with a Backtrack4 liveDVD, but it told me I didn't have the correct permissions to save the changes to the file.

 

Please help.

[Dj TweeX]

I installed OS X 10.5.7 on an older Dell that I had sitting around.

 

While trying to add a custom display resolution, something went wrong. I added 2 lines of code to a system file, and rebooted. Exactly how stupid my mistake here was isn't really important.

 

After it gets through the BIOS, the bootloader immediately attempts to change the resolution to the custom resolution I edited. For whatever reason, this doesn't work and causes it to crash. There is absolutely no opportunity to do anything at all before it crashes and reboots.

 

All I need to do is remove those 2 lines of code. How the do I do it? I tried booting it with a Backtrack4 liveDVD, but it told me I didn't have the correct permissions to save the changes to the file.

 

Please help.

 

linux cant mount a HFS+ drive with read write.

you have to boot a OSX dvd and goto disk utility. turn off journaling for the drive.

then you can mount it with read write and fix the file