Shell Programming and Scripting

#!/bin/ksh
PATH=  /usr/
if [ -d $PATH ]
then
  echo "is a directory"
  filename = $ls -ltr | tail -1
fi

#!/bin/ksh
PATH=/usr/
if [ -d $PATH ]
then
  echo "is a directory"
  filename=$(ls -ltr | tail -1)
fi

#!/bin/ksh
PATH= /www/a/temp/in/
if [ -d $PATH ]
then
#it should copy the contents of latest file in the specified path into a variable, say for example filename
fi

#!/bin/ksh
PATH=/full/path/to/your/target/directory
cd $PATH   #go in that directory
filename=$( ls -lrt | tail -1 | awk '{print $7}') #variable contains name of latest file
file_content=$(cat $filename) #this variable contains content of that file...
echo $file_content #to see the output

#your code.....=>
if [ -d $PATH ]    # I didn't understand your purpose of checking the directory here...
then
  echo "is a directory"
  filename=$(ls -ltr | tail -1)
fi