#   This program is free software: you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation, either version 3 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
shopt -s lastpipe
echo -e 'A\nB' | while read letter; do
    echo -e '1\n2' | while read digit; do
        echo $letter$digit
    done
done

myPipefunc()
{
    cat | tee $TMPDIR/outfile
}
echo HI | myPipefunc

echo -e 'A\nB' | while read letter; do
    echo -e '1\n2' | while read digit; do
        echo $letter$digit | myPipefunc
    done
done

rm -f $TMPDIR/outfile

unset -f myPipefunc
myPipefunc()
{
    cat | read var
    return 42
}
echo HI | myPipefunc

echo $var -- $? -- ${PIPESTATUS[@]}