at/cron treatment of groups

[Jan Purchase]

Hello,

I am not too well versed with some of the vagaries of SVR2 but would
anyone explain why a job scheduled to run by at or cron under uid x
does not run with all of x's group permissions.

for example:

	mac% who am i
	admin     ttyC1           Jun 10 9:51
	mac% groups
	user bin sys root src
	mac% at now + 1 mins
	echo "my groups are `groups`" > ttyC1
	^D
	mac% my groups are user

It seems that jobs initiated by cron or at have access restricted to
their first group. Is there any valid reason for this? Security maybe?

any help appreciated.
Cheers
Jan.