Good code snippet to run or die in shell script.

pass_or_die.sh

(autoconf --version) < /dev/null > /dev/null 2>&1 || {
    echo
    echo "You must have autoconf installed to compile $PROJECT."
    echo "Install the appropriate package for your distribution,"
    echo "or get the source tarball at http://ftp.gnu.org/gnu/autoconf/"
    DIE=1
}


autoconf || exit $?