i have a perl script. which does some task. u shouldnt be worried about what it does.

what i want is that the moment the user is authenticated, the login program should start the PERL script instead of launching the bash shell.

at the same time i want to disable the escape sequences. like CNTRL+Z and CNTRL+C

so that the user remains with in the PERL script.

the objective of this futile exercise is that i dont wan the user to know that i am actually running a bash shell underneath. i wan him to have a feeling that this is my own OS.

thats why he should never be able to come out of that script and have a look at other things in his home directory.

$ sed -i -e 's,/bin/bash,/bin/myscript.pl' /etc/passwd
(but read the man pages first )

sure i ll love to read the man pages.

can u name the command for which i read the man pages?

or just the topic which i can search on the internet to have a know how of this problem?

$ man /etc/passwd
$ man sed # if you don't know what it does--it's a wondertool
google('/etc/passwd')

/etc/passwd contains the usernames and encrypted passwords.

sed is stream line editor.

this still doesnt answer my question as to how can i redirect the login program to launch my perl script instead of launching the bash shell.

oh. Actually I directed you to the wrong manpage:
$ man 5 passwd
look at the file. Understand what sed does. make a copy and do the sed on the copy.

hth --Jonas

thanks i got it now.

just wanted to know how sed would help in this situation?

like i just have to replace the shell field with my perl script.

what has sed go to do with this?

doing it programatically instead of by hand.

ok here is the passwd file in /etc

so as u can see i have directed the shell to bash.pl.

now all this bash.pl does is to print a hello world message.


so when i try to logon the putty program just exits .

what should i do so that the program shouldnt exit.

print $_ while (<STDIN>);

thanks a lot.

now one more thing.

how to disable CNTRL+C nd all the SIGS which cause the program to terminate.

i dont wan the user to come out of this script and roam around the file system.

i know this can be done through other ways but i wan it this way.

by the way when i pressed CNTRL+C putty just exited all on its own.

it seems that i dont have to worry about this. right?

$ man login # and others, but I can't remember which offhand
basically, when your script exits, the user will be logged out (just like when bash terminates).

so you (probably) don't have to worry about ^C and ^Z -- though I'd find it inconvenient to get logged out by a random keypress.

if you want to catch the signals (SIGINT and SIG???), look at perls signal handling.

yeah u are right.

the script should just do nothing if a user wrongly types in CNTRL+C.

this script should handle all kill SIGS.

thanks