Boot Flag Descriptions

[jshanh]

Not sure where to put this one in the forum, so sorry for creating a new discussion.
I have googled for the answer to these questions and apologize if they are obvious or not, but I was wondering what exactly a couple of boot flags do?
in know what -v -x -s -f does,
but not -legacy(something about 32bit mode?, my computer runs fine whether its on or off, i have a 64 bit cpu, does that matter?)
and not -system=X86PC (same as above, my computer runs fine either way so it seems to me.)

What do you guys recomend I do, and what actually is running differently in the background that I cant tell for either boot flag?
I would love to know so I can tweak and fully utilize the hardware I have.
Thanks in advance.

[zephyroth]

Hi,

As far as I know the "-legacy" flag force Leopard to boot in 32 bits mode.
With mach_kernel 9.0.0 SSE2/SSE3 if you don't put this bootflag in com.apple.Boot.plist Leopard will not boot.
With mach_kernel 9.1.0 SS3 you can boot without that flag but this kernel seems to be modified to boot in 32 bits mode only.

You can verify if your system is in 32/64 bits mode using GeekBench.

The "-system=X86PC" (I thought it was "-platform=X86PC") tells Leopard that you're booting on an i386 machine so it must only load i386 code and not ppc code.

[jshanh]

ahhhh, Thanks

[ShadeZeRO]

With mac_kernel 9.1.0 SSE3 ...even without the -legacy string it will boot 32bit mode. It's just safer to have it in there as to not cause conflicts.

[jshanh]

Yes, I put back the -legacy string, and things do seem to run smoother and faster. Thanks

[Snow]

So does that mean with an older kernel we can boot in 64bit mode?

That's the only bit I would like to see fixed.