source: vendor/bash/3.1-p17/examples/functions/keep

# From: Seth Chaiklin <psykseth@aau.dk>
# To: chet@ins.CWRU.Edu
# Subject: bash functions (sorta)

#
# keep:
# usage: keep program
# declare the a program should be "kept".  i.e. try to fg a stopped one
# and only when that fails start a fresh program.
#

keep()
{
        case $# in
        1|2)    ;;
        *) echo "usage: keep [alias] program" 1>&2 ; return 1;;
        esac

        # progname
        pn=${1##*/}

        # set up an alias for the kept program
        if [ $# = 1 ]; then
                alias "$pn=fg $1 2>/dev/null || $1"
        else
                alias "$1=fg $2 2>/dev/null || $2"
        fi
}

#
# unkeep:
# usage: unkeep program
# unset the alias set up by the keep function
#

unkeep()
{
        if [ $# != 1 ]; then
                echo "usage: unkeep program"
                return 2
        fi

        # unset the alias for the kept program
        unalias "${1##*/}"
}

#
# kept:
# lists all kept programs in 'alias: program' form
#

kept()
{
        alias | grep "fg.*2>" | sed "s/alias \(.*\)='fg.*||\(.*\)'$/\1:\2/"
}


# some things that should be kept
#keep /usr/local/bin/emacs
#keep e ${EDITOR:-/usr/local/bin/emacs}
#keep edit ${EDITOR:-/usr/local/bin/emacs}
#keep /usr/local/bin/emm