ref: a8462d5114f895b5fd937736d92c6ff148bec0a5
dir: /util/savehist/
#!/bin/rc
# savehist - prune and save command history
# usage: savehist
rfork ne
temp=/tmp/quit-$pid
hist=$home/lib/text
touch $hist
#sigexit{ rm -f $temp }
grep 'term% ' /dev/text > $temp
cat $temp $hist | sort | uniq > /tmp/TMP-$pid
mv /tmp/TMP-$pid $hist
rm -f $temp