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Figure 5	Listing 1	Listing 2	Listing 3	Listing 4	sep93.tar

Listing 2: Sample /etc/profile

#
# Sample /etc/profile
#
trap '' 1 2 3   # turn off signals ... they are ignored
#
# ... system commands here
#
#
# track login
LOGNAME=`logname`
TTY=`tty`
export LOGNAME TTY
echo "LOGIN .$LOGNAME.$TTY.`date`" >> /usr/adm/logins
trap 1 2 3   # signals are restored
#
# set the trap for logout
#
trap "/usr/local/checkout $LOGNAME $TTY" 0