That's an excellent question.
Try /Applications/Utilities/Console
The log file may be stored in /Volumes/$(Targeted_Disk_Mode)/var/log/system.log
where $Targeted_Disk_Mode refers to the mac you're targeting
Note that the mac likes to hide the /var subdirectory
you can open it by using the 'open' command in terminal mode
Typhon:~ jeremy$ open /Volumes/Macintosh\ HD/var/log
will bring it up in the finder
or even
Typhon:~ jeremy$ open /Volumes/Macintosh\ HD/var/log/system.log
which will open the logfile in Console
Note the backslash-- that's how you can enter spaces on the command line..
Let me know if it works. I haven't had to do this yet...
Ok, what’s in this log is not the kernel panic on boot but apparently the last thing the computer was doing when my mother started having problems (Safari seemed to freeze up) and she killed everything by long pressing the power button.
Nov 15 15:06:49 macintosh iTunes[5332]: tid:3ef37 - Mux ID not found in mapping dictionary
Nov 15 15:06:49 macintosh iTunes[5332]: tid:3ef37 - Can't handle disconnect with invalid ecid
Nov 15 15:06:52 macintosh logd[75]: Power button HID event - flushing proactively
Nov 15 15:06:54 --- last message repeated 1 time ---
Nov 15 15:06:54 macintosh com.apple.xpc.launchd[1] (com.apple.xpc.launchd.domain.user.501): Service "com.apple.xpc.launchd.unmanaged.loginwindow.106" tried to register for endpoint "com.apple.tsm.uiserver" already registered by owner: com.apple.SystemUIServer.agent
Nov 15 15:21:59 --- last message repeated 1 time ---
Nov 15 15:21:56 macintosh syslogd[57]: ASL Sender Statistics
Nov 15 15:22:00 macintosh timed[95]: settimeofday({0x5bedd568,0x74992}) == 0
Nov 15 15:22:05 macintosh timed[95]: settimeofday({0x5bedd56d,0x78587}) == 0
Nov 15 15:22:07 macintosh com.apple.xpc.launchd[1] (com.iospirit.candelair.sync): Service only ran for 3 seconds. Pushing respawn out by 7 seconds.
Nov 15 15:57:54 macintosh syslogd[57]: ASL Sender Statistics
Nov 15 15:57:57 macintosh timed[95]: settimeofday({0x5bedddd5,0xe8b34}) == 0
Nov 15 15:57:59 macintosh timed[95]: settimeofday({0x5bedddd7,0x12db0}) == 0
Nov 15 15:57:59 macintosh com.apple.xpc.launchd[1] (com.apple.imfoundation.IMRemoteURLConnectionAgent): Unknown key for integer: _DirtyJetsamMemoryLimit
Nov 15 15:58:01 macintosh com.apple.xpc.launchd[1] (com.iospirit.candelair.sync): Service only ran for 1 seconds. Pushing respawn out by 9 seconds.
Nov 15 16:16:04 macintosh syslogd[57]: ASL Sender Statistics
Nov 15 16:16:07 macintosh timed[95]: settimeofday({0x5bede217,0xc3af7}) == 0
Nov 15 16:16:07 macintosh com.apple.xpc.launchd[1] (com.iospirit.candelair.sync): Service only ran for 3 seconds. Pushing respawn out by 7 seconds.
Nov 15 16:16:11 macintosh timed[95]: settimeofday({0x5bede21b,0x4100f}) == 0
Nov 15 16:16:15 macintosh com.apple.xpc.launchd[1] (com.iospirit.candelair.sync): Service only ran for 0 second. Pushing respawn out by 10 seconds.
I just copied the last part of it till it ends.
I notice that it references (com.iospirit.candelair.sync). This is also the kext it reports in the verbose boot before it kernel panics.
Candelair is a software program that worked with the older iMacs with IR remotes. This is basically junk left over from years ago that I thought had been uninstalled. If this is the culprit how do I stop it from being loaded as kext at boot up by accessing the disk via target disk mode? Let me know whether coping more of this log will help.
[doublepost=1542849740][/doublepost]Could it be that this leftover bit of software was trying to run and my mother pulled the plug and corrupted it?
Can I get to 3rd party kexts via target disk mode and delete them so macOS doesn’t try to load them on boot? Where are they located?
[doublepost=1542850690][/doublepost]That was it.
Problem solved. I went into Library/Extensions via Target Disk Mode and deleted RBIOKitHelper.kext and the next boot went off without a hitch.
Thank you all.