|u = the file’s user (you)||r = read access|
|g = the file’s group||x = execute access|
|o = others||w = write access|
|a = the user, the group, and others|
To change permissions for a file named filename.cgi, you need to chmod the file (change mode). For example, when you type this:
chmod u=rwx,g=rx,o=rx filename.cgi
read, execute, and write access to the user (that’s you)
read and execute access to the group and
read and execute access to others
Some scripts will tell you to chmod 775 (for example). Doing the above is the same thing as typing chmod 775. You can use either method with our Unix servers. Let me explain:
When using the numeric system, the code for permissions is as follows:
r = 4 w = 2 x = 1 rwx = 7
The first 7 of our chmod775 tells Unix to change the user’s permissions to rxw (because r=4 + w=2 + x=1 adds up to 7. The second 7 applies to the group, and the last number 5, refers to others (4+1=5).
When doing an ls -l on the file, telnet always shows the permissions this way:
Ignore the first dash, then break up the above into three groups of letters. If there’s a dash where a letter should be, it means that there is no permission for those people.
Remember: the first 3 apply to user, the second 3 apply to group, and the third 3 apply to others.