correct shell and rc file handling

#! /bin/sh

SHELL=`readlink -f /proc/$$/exe | cut -d/ -f3`

#default install location (root)

if [[ -z $prefix ]]; then prefix="/usr/local/share"; fi

echo "installing to: $prefix"

# create install directory

INSTALLDIR="${prefix}/universc-${version}"

echo "Installing to $INSTALLDIR"

mkdir -p ${prefix}/universc-${version}

#requires root priviledges

if [[ -w ${INSTALLDIR} ]]

    then

    rsync -arutvxz * ${prefix}/universc-${version}

    export PATH=${prefix}/universc-${version}:$PATH

    echo "universc-${version} added to PATH"

    SHELL_RC=`echo ~/.${0}rc`

    echo "export PATH=${prefix}/universc-${version}:$PATH" >> $SHELL_RC

    echo "universc-${version} added to PATH automatically in new $0 shell session"

    rsync -arutvxz * $INSTALLDIR

    export PATH=$INSTALLDIR:$PATH

    echo "${INSTALLDIR} added to PATH"

    SHELL_RC=`echo ~/.${SHELL}rc`

    echo "export PATH=:${INSTALLDIR}:\$PATH" >> $SHELL_RC

    echo "universc-${version} added to PATH automatically in new ${SHELL} shell session"

    echo "run the following to add it to your shell of choice"

    echo "    export PATH=${prefix}/universc-${version}:$PATH >> ~/.bashrc"

    echo "    export PATH=${INSTALLDIR}:\$PATH >> ~/.${SHELL}rc"

    echo "universc-${version} has been installed it can be run as follows"

    echo "    launch_universc.sh"

    launch_universc.sh --version

    echo "      sudo bash $( cd -P "$( dirname ${BASH_SOURCE[0]})" >/dev/null 2>&1 && pwd )/INSTALL"

    echo "      sudo make install"

fi

source ~/.${SHELL}rc

prefix=`cat inst/.installed`

echo "uninstalling from: $prefix"

exit 0

# add manual directory to PATH if not already found

## check config for Linux

if [[ -f /etc/manpath.config ]]