#   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 extdebug

callstack(){
 deep=${#BASH_ARGV[*]}
 echo "deep $deep"
 i=0
 for ff in ${BASH_ARGV[@]}
 do
  echo "$i $ff"
  i=$(($i+1))
 done
}

f3()
{
	echo $FUNCNAME: calling callstack
	callstack
	echo FUNCNAME stack: ${FUNCNAME[@]}
	caller 0
	echo $FUNCNAME: returning
}

f2()
{
	echo $FUNCNAME: calling f3
	f3 3 z
	echo $FUNCNAME: return from f3
}

f1()
{
	echo $FUNCNAME: calling f2
	f2 2 y
	echo $FUNCNAME: return from f2
}

echo main: calling f1
f1 1 x
echo main: f1 returns