mach_kernel appeared

DO NOT mess with /mach_kernel. It is the heart of Mac OS X and absolutely essential.

mach_kernel should have the 'hidden' as shown below via the 'ls' command in an Applications -> Utilities -> Terminal session:

/bin/ls -leO@ /mach_kernel

-rwxr-xr-x@ 1 root wheel hidden 8394688 Dec 17 22:06 /mach_kernel

com.apple.FinderInfo 32

Did you tell your Finder to show hidden files? If so that would explain why you are seeing mach_kernel

It does NOT hurt anything if you see mach_kernel, as long as you DO NOT mess with it. If you can avoid that temptation, then you can leave it alone.

You might consider running Applications -> Utilities -> Disk Utility -> Repair Permissions. That might fix up the 'hidden' flag if you have not told the Finder to show hidden files.

The file should be hidden. Open Terminal and copy/paste the following command into the Terminal window:

sudo chflags hidden /mach_kernel

Press return. It will ask for your admin password. Enter that and press enter again.

tjk wrote:

Before I hide it though, do you know for sure it's in the right place?

Based on your description, the mach_kernel file is in the correct place. mach_kernel exists in the root directory of your file system, on the disk you boot from. If you have only one disk in use in your file system, then mach_kernel will be located in the root ("/") directory of that disk.

You're welcome. 🙂

I had the same problem with additional problem.

I have 10.9.5 & just downloaded the security update(2015-002) and also now have this kernel in the root level of Mac HD. I almost trashed it, then thought I better come here to see if there is any info on it.

So I did the terminal thing, entering: sudo chflags hidden /mach_kernel, hit return, and I get this:

Sorry, try again.

Password:

I have don't have a password on my system, and have used terminal before without a password and it worked fine. I normally hit return for the password but now I can't do this. Do I have to create a password to follow through on this?

Thanks

Robes

System Specs:

2010 (mid May) iMac 27”/4850-512M

Processor: 065-9233 2.8GHz Quad-Core Intel Core i7;

Memory: 065-9266 8GB 1066MHz DDR3 SDRAM-2x4GB;

Hard Drive: 065-8407 2TB Serial ATA Drive;

Graphics: 065-8981 ATI Radeon HD 4850 512MB

OPTICAL DRIVE 065-9410 8X DOUBLE-LAYER SUPERDRIVE

OS: 10.9.5 Mavericks

It sounds like you may have upgraded your Mac from Snow Leopard or earlier. In those versions of OS X, you can have a null admin password. If you upgrade from there, it remains that way. However, you can't have a null password for Lion (may have started with SL) and later for the Terminal. Your admin password must have some kind of character to actually type in. You can't just press the Enter key and continue.

Or, you're in a non admin account. Entering the password for a Standard account isn't what Terminal is looking for. It wants the admin account password.

I did upgrade from SL to Mavs. I went in & created a password and that allowed me to enter the Terminal command and the mach kernel is now hidden.

Thanks

Excellent. 🙂

Well, I too just applied the 2015-002 update and noticed that file appeared in the Computer tab. My Mavericks was updated from SL about a month ago.

So, does this mean there was minor bug in this update that didn't get caught? I'm guessing others have this (at least those that went from SL to Maverics) probably have this but haven't noticed yet.