In PuTTy or Terminal, you must change permissions using the ‘chmod’ command. The syntax for the command is as follows:

chmod ### filename

In this command, each number specifies the permissions for one of three groups. The first number sets permissions for the owner of the file, the second sets permissions for groups of other users, and the third sets permission for the rest of the world.

When you set permissions for a group, you will set it to a number 0-7:

0=No Permissions Whatsoever

1=Execute Only

2=Write Only

3=Write and Execute

4=Read Only

5=Read and Execute

6=Read and Write

7=Read, Write, and Execute

Examples:

If you would like to make a file in your UNIX account only readable by other users and the world, your chmod command might look something like this:

chmod 744 test.doc

If you would like the file to be fully readable and modifiable by everyone, your chmod command would look like this:

chmod 777 test.doc

Be careful when setting permissions on files, as setting the wrong permissions may prevent other users from viewing your websites or may make it impossible for you to modify a file until permissions are corrected.