#!/usr/bin/ksh
a = "good script " # There cannot be spaces between variable name and assignment 
cd $APPS # APPS needs to have an assignment before use or it will be empty
ls -l *.txt | while read $txt # $ is to deference a variable (the value in a variable). Remove the $. Also remove the -l out of ls, that would output extra that it will interfere
do
	if [grep -q 'a' txt] then # txt is the variable name, you want the value in the variable. It needs $txt
		cp $APP/*.txt cp $HIST/*.txt # $APP is not the same than $APPS. In any case $APP and $HIST have not been declared before in the script
                 # * is a glob to indicate anything. *.txt will mean file1.txt file2.txt, file3.txt. You do not want that. You want just $txt
                 # There must be spaces between [ grep ... ]
                 # There must be a semicolon before the then
         else
		rm $APP/*.txt # apply the same comments from above
		echo "Exit successfully"     
        fi
done