UNIX for Dummies Questions & Answers

I'm writing this command/script to allow students to vi a private file of mine
in a private directory of mine. chmod 700 dir chmod 660 file

however since i own the directory and file; the script has to be ran by me so to speak, im just not sure how to set about doing this.

the script is simple enough

chmod 777 directory


but the script would only execute these statements for me. How do I get it to work for someone else? short of changing the owner to root or something like that

You would need to write a binary executable to implement something like this.

To run something with your uid (as you) the suid bit is required.

The suid is only valid for binary executables and not for scripts.

this is a description of the assignment, your responses have led me to believe he's given us something impossible to do. I'll ask him to clarify this in an email but I wanted to be sure I know exactly what I'm asking.

assignment:
write a command which will allow any students to vi (including modify) a private file (owned by you, perms 660) in a private directory (owned by you, permissions 700)

Now you're saying what he's asking is impossible to do? Don't mean to bug anyone

That depends completely on the OS. For example this: will allow me to modify the file as another user using test.sh as a wrapper on Solaris.

Code:

 6843    1 drwxr-xr-x   3 reborg   other         512 Mar  6 00:07 /home/reborg/
 6844    1 drwx------   2 reborg   other         512 Mar  6 00:04 /home/reborg/test
 6846    1 -rw-rw----   1 reborg   other          13 Mar  6 00:07 /home/reborg/test/test
 6847    1 -rwsr-sr-x   1 reborg   other          38 Mar  6 00:05 /home/reborg/test.sh

Not on my Solaris unless test.sh is a binary executable.

thanks guys, it turns out it wasn't as difficult as I thought it would be
I just needed to set the s-bit on my script
I wasn't using setid in it
it turned out fine
now I can go watch heroes again