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Mac OS X does not seem to dump the exact output of dmesg to a file. I need to log the dump of dmesg to the disk.

kernel.log and system.log do not contain the required information. Only output of dmesg tells me which file failed to read from a faulty drive.

Compare output in kernel.log:

Oct 25 19:28:31 The-Evil-Lion kernel[0]: disk0s2: I/O error.

with the output of dmesg:

         0 [Level 3] [ReadUID 0] [Facility] [ErrType IO] 
[ErrNo 5] [IOType Read] [PBlkNum 338383504] [LBlkNum 0] [FSLogMsgID 626287415] 
[FSLogMsgOrder First] 
         0 [Level 3] [ReadUID 0] [Facility] 
[DevNode /dev/disk0s2] [MountPt /Volumes/Macintosh HD] 
[Path /Volumes/Macintosh HD/Users/user/Library/Preferences/ByHost/] 
[FSLogMsgID 626287415] [FSLogMsgOrder Last] 

(newlines added for readability)

Actual issue is that I cannot type dmesg during the boot, for obvious reasons. Dumping the dmesg to a file during boot would be extremely helpful.

share|improve this question
This link is related:… – yoydigg3r Nov 9 '11 at 0:58
@MathewEley Not really: look at my comments over there and re-read my question. Console output is not the same as the contents of those files. – Ivan Vučica Nov 9 '11 at 20:16

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