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I'm new to Ubuntu. I installed it because i'm using it in my operating systems class in college. One thing needed to do is copy. This is the lecturers notes on how to do this:
Change to your home directory


Display a listing of the files contained within it in long format

ls -al

Make a directory here called test

mkdir test

Below test create two directories x and y

cd test
mkdir x
mkdir y

Copy the file fstab from the /etc directory to the directory y

cd y
cp /etc/fstab .

But it's not working. Can anyone help me with this?

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you might want to check the permissions of the /etc directory using ls -ld /etc for umask of 002 it must be rwx-r_x-r_x(755). – Ankit Oct 14 '12 at 17:46
@OliveTwist Just the copy step everything else is fine. – Pendo826 Oct 14 '12 at 17:54
@Ankit Thanks man. yeah its read/write – Pendo826 Oct 14 '12 at 17:54
@Ankit I suggest you to add an answer with a bit more details. It will help future visitors – Anwar Shah Oct 14 '12 at 18:00
up vote 1 down vote accepted

In order to copy a file you must have read permission on the parent directory of the file and write permission on the destination.

Think of directory as a container with a lock and file as contents of the container.

You must have an access to the keys of the lock in order to access the file inside the directory(container).

File Permissions:-

r - can read the file.

w - can write to a file.

x - can run the file as a program.

Directory Permissions:- 

r - can read the contents of the directory.

w - can make changes to files inside the directory/ add or delete the files.

x - can cd to a directory.

Directory permissions are important and can override the file permissions.

Even if you're file doesn't have read permissions but the parent directory of the file has a read permission than you can copy the file assuming that you're copying the file to a location where you can write.

I assume this might be helpful.

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