#!/bin/sh -x
FILE1=$1
FILE2=$2
FILE3=$3
FILE4=$4

prog1.pl $FILE1 $FILE2
STATUS=$?
if [ $STATUS != 0 =; then
 set +x
 echo "Belch in prog1.pl: $STATUS"
 exit $STATUS
fi

prog2.pl $FILE2 $FILE3
STATUS=$?
if [ $STATUS != 0 =; then
 set +x
 echo "Belch in prog2.pl: $STATUS"
 exit $STATUS
fi

prog3.pl $FILE3 $FILE4
STATUS=$?
if [ $STATUS != 0 =; then
 set +x
 echo "Belch in prog3.pl: $STATUS"
 exit $STATUS
fi