"mount -a -t nfs" problems found and solved

[Chris Siebenmann]

 Well, I found the cause of the problem we were having with "mount -a
-t nfs" getting a SIGSEGV. It turns out that the DS3100 mount is
somewhat stricter (in a sense) about malformed /etc/fstab lines
(although I wish it gave an error message!). We like to automatically
generate various files here (with 9 clients and 2 servers plus the
outside world it becomes a lifesaver when you shuffle NFS mounts
around), so I had an /etc/fstab with the lines

	# This is a machine-generated file. Please, fix the master
	# template (~cks/adm/templates/fstab.template) and regenerate
	# it instead of hand-editing.

at the start (minus the tabs), on the idea/principle that a) many
things take "#" as a commend and b) the local Suns do the same thing
and it works for them. This works on Vaxen, but not on DS3100's; they
seem to dereference a null pointer during a strcmp(). Since it happens
only with a -t specified, I assume it's checking the file system type.

 My solution was to tack six ":"'s on, to make the comment lines valid
(albeit unusual) /etc/fstab entries. Then everything works fine. Maybe
we can persuade DEC to recognize comments in /etc/fstab in the next
release...

-- 
	"I shall clasp my hands together and bow to the corners of the world."
			Number Ten Ox, "Bridge of Birds"
Chris Siebenmann		...!utgpu!{ncrcan,ontmoh!moore}!ziebmef!cks
cks at white.toronto.edu	     or ...!utgpu!{,csri!}cks