RE: In-kernel process exit hooks?

[Paul Goyette <paul%vps1.whooppee.com@localhost>]

On Thu, 7 Jan 2016, Terry Moore wrote:

> Will the hang occur if make dies due to a signal (control-C, or kill -9, for
> example)?

It depends on which fd is numerically lower.  If the /dev/filemon fd is 
lower, it will get closed first, which removes the reference to the 
log-file fd.  If the log-file fd is numerically lower, it will get 
closed first, and will hang waiting for its reference count to clear.

In practice, I expect that make(1) will open /dev/filemon first, get an 
fd, and then open the log file and get another fd.  The fd's are 
assigned on a first-free basis, so /dev/filemon gets the lower number, 
and no crash.  But no guarantee, either!


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