if test -z $GSDLOS ; then
  GSDLOS=`uname -s | tr '[A-Z]' '[a-z]'`
  # check for running bash under cygwin
  if test "`echo $GSDLOS | sed 's/cygwin//'`" != "$GSDLOS" ;
  then
    GSDLOS=windows
  fi
  export GSDLOS
fi


run_untar()
{
  local package=$1
  local version=$2
  local ext=$3

  tar_args="";

  if [ $ext = ".tar.gz" ] ; then
    tar_args="xvzf"
  elif [ $ext = ".tgz" ] ; then
    tar_args="xvzf"
  elif [ $ext = ".tar.bz2" ] ; then
    tar_args="xvjf"
  elif [ $ext = ".tar.bz" ] ; then
    tar_args="xvjf"
  elif [ $ext = ".tar" ] ; then
    tar_args="xvf"
  else 
    echo "Warning: Unrecognized extension: $ext"
    echo "Assuming tarred, gzipped file"
    tar_args="xvjf"
  fi


  echo tar $tar_args $package$version$ext 
  tar $tar_args $package$version$ext

  if [ $? != 0 ] ; then
    echo "      Error encountered running *untar* stage of $progname"
    exit 1
  fi
}

opt_run_tarclean()
{
  local type=$1
  local package=$2
  local version=$3

  if [ $type = "1" ] ; then

    local dir=$package$version
    if [ -d $dir ] ; then
      echo /bin/rm -rf $dir
      /bin/rm -rf $dir

      if [ $? != 0 ] ; then
        echo "      Error encountered running *tarclean* stage of $progname"
        exit 1
      fi
    else 
      echo "Unable to find directory $dir"
    fi
  fi
}

opt_run_untar()
{
  local force_untar=$1
  local auto_untar=$2
  local package=$3
  local version=$4

  local ext="";

  if [ ! -z "$5" ] ; then
    ext=$5
  else 
    ext=".tar.gz"
  fi

  if [ $force_untar = "1" ] ; then
    run_untar $package $version $ext
  elif [ $auto_config = "1" ] ; then
    if [ -d $package$version ] ; then
      echo "Found untarred version of $package$version$ext => no need to untar"
    else
      run_untar $package $version $ext
    fi
  fi
}


opt_run_configure()
{
  local force_config=$1
  local auto_config=$2
  local package=$3
  local version=$4
  local prefix=$5
  local opt_args="";

  if [ ! -z "$6" ] ; then
    opt_args=$6
  fi

  if [ $force_config = "1" ] ; then
    echo "[pushd $package$version]"
    ( cd $package$version ; \
      echo ./configure --prefix="$prefix" $opt_args ; \
      ./configure --prefix="$prefix" $opt_args )
    if [ $? != 0 ] ; then
        echo "      Error encountered running *configure* stage of $progname"
        exit 1
    fi
    echo "[popd]"
  else
    if [ $auto_config = "1" ] ; then
      echo "Found top-level for ${progname%.*} => no need to run ./configure"
    fi
  fi
}


opt_run_make()
{
  local type=$1
  local package=$2
  local version=$3
  local opt_target=""

  if [ ! -z "$4" ] ; then
    opt_target=$4
  fi

  if [ $type = "1" ] ; then
    ( cd $package$version ; \
      make $opt_target)

    if [ $? != 0 ] ; then
        echo "      Error encountered running *make $target* stage of $progname"
        exit 1
    fi
  fi
}



force_untar=0
auto_untar=0

force_config=0
auto_config=0

compile=0
install=0
clean=0
distclean=0
tarclean=0

if [ $# -gt 0 ] ; then
  for cmd in $* ; do
    echo $cmd
    if   [ $cmd = "untar" ] ;     then force_untar=1
    elif [ $cmd = "configure" ] ; then force_config=1
    elif [ $cmd = "compile" ]   ; then compile=1
    elif [ $cmd = "install" ]   ; then install=1  
    elif [ $cmd = "clean" ]     ; then clean=1  
    elif [ $cmd = "distclean" ] ; then distclean=1
    elif [ $cmd = "tarclean" ] ;  then tarclean=1
    fi
  done
else
  # defaults
  auto_untar=1
  auto_config=1
  compile=1
  install=1
  clean=0
  distclean=0
  tarclean=0
fi

if [ $auto_config = "1" ] ; then
  if [ ! -e $package$version/Makefile ] &&  [ ! -e $package$version/config.h ] ; then
    force_config=1
  fi

fi