shell script problems

mtest · 10-23-2003, 08:15 AM

there are 3 questions. pls reply this

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how to execute wall command in shell script
how to pass messages to users logged in thru wall command from shell script
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how to change directory(cd command) from shell script
for eg:
in shell script i have given cd/home
but when i execute shell scipt the directory remains the same with out change.
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how to flash a message when user logs in
desc:
to give a message from root to a particular user so that when ever the user logs in, the first message must be "Contact System Administrator" and system should not allow the user to do any thing further. only message should be flashed
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thanks in advance

Tarts · 10-23-2003, 08:37 AM

1)

Code:

#!/bin/bash
echo "This is a message to all users." | wall

This already send's it to all user's.

2)

I think the script is run in a subshell, so it won't change the directory of the person running the script.

3) The only thing I found was '/etc/nologin', which can be used to prevent user login and give the user's a message, just add the message in '/etc/nologin'...unfortunatly, that would prevent all users.

However, what you could do is 'write' to the specified users terminal, notify them to see you, then lock their password with 'usermod -L <username>'.

That's the best I can come up with.

Tarts · 10-23-2003, 11:11 AM

Code:

if [ "$UID" = 1000 ]; then
  echo "See system admin." | write stratus
  usermod -L stratus 2> /dev/null
  echo "root, stratus logged in." | write root 2> /dev/null
  logout
fi

Add this to '/etc/profile', change the parts in bold, such as '"$UID"' , 'echo $UID' to get this info about the user. Change the:

'echo "See system admin." | write <user>',

and

'echo "root, <user> logged in." | write root'

aswell as :

'usermod -L <user> 2> /dev/null'.

Enjoy.

Tarts.

jim mcnamara · 10-23-2003, 12:25 PM

2) it is exec'ed or forked so that when it returns the old current directory is restored.

The only way to do this is to change the user's default directory
before they log in. I'm assuming you want certain users to be blocked from their home directories at login.

Tarts · 10-23-2003, 12:36 PM

Quote:

Originally posted by jim mcnamara
2) it is exec'ed or forked so that when it returns the old current directory is restored.

The only way to do this is to change the user's default directory
before they log in. I'm assuming you want certain users to be blocked from their home directories at login.

From what I gather mtest wants to not allow the user to do anything..

jim mcnamara · 10-23-2003, 01:57 PM

Then why not just disuser the guy(s)/girl(s) ?

This is a waste of his time

silatts · 10-25-2003, 09:25 AM

q3)

do not try doing it in the /etc profile - as it can be escaped from,,

..

make a new 'shell'

Code:

cat >> /usr/local/bin/goawayshell
#!/bin/sh
echo go away
exit 0

cntrl D

chmod 555 /usr/local/bin/goawayshell

now in the password file - set certain (or all?!?) users shell to /usr/local/bin/goawayshell - I think that is reasonably safe to do... but I haven't tried it...

Sil

silatts · 10-25-2003, 09:27 AM

Quote:

Originally posted by jim mcnamara
Then why not just disuser the guy(s)/girl(s) ?

This is a waste of his time

yeah - it would appear so,. easier to no access them an b4 the login prompt put a message saying if you can't login contact admin?

Sil

Tarts · 10-25-2003, 04:26 PM

Quote:

Originally posted by silatts
yeah - it would appear so,. easier to no access them an b4 the login prompt put a message saying if you can't login contact admin?

Sil

That sounds better, I found '/etc/issue' where you can put a message seen before the login prompt.

Tarts