@comment $FreeBSD$
bin/ksh93
@exec echo "updating /etc/shells"; cp /etc/shells /etc/shells.bak; (grep -v %D/%F /etc/shells.bak; echo %D/%F) >/etc/shells; rm -f /etc/shells.bak
@unexec echo "updating /etc/shells"; cp /etc/shells /etc/shells.bak; (grep -v %D/%F /etc/shells.bak) >/etc/shells; rm -f /etc/shells.bak