How to check files in Backtrack

How to check files in Backtrack

Write a script, which copies file1 to file2, check to see whether file2 exists already, if file2 exists then check that whether there is write permission on file2 or not, if there is write permission on file2 then warn user before copying file1 to file2, and get permission to proceed else exits, otherwise copy files.

Code

#!/bin/bash

clear

echo " ==== File Copying Program ==== "

echo " "

echo "These are the files in present directory"

ls

echo ""

echo "Please enter source filename "

read a

vre=`pwd`

if [ -f $vre/$a ];

then

echo " "

else

echo "Enter valid file name"

exit 0

fi

echo "Please enter destination filename "

read b

vre1=`pwd`

if [ -f $vre1/$b ];

then

echo "File dont have write permissions"

echo "Do you want to change mode and allow writting ? , (y)es or (n)o "

read d

case $d in

y)

chmod 600 $b

cp $a $b

echo " File Copied Successfully"

exit 0

;;

n)

exit 0

;;

esac

else

echo "File Name Invalid in present directory"

exit 0

fi

else

echo "Enter valid file name"

exit 0 

Screen Shot