Menu bashed shell script for users shell

0.o · 07-17-2008, 10:08 AM

hello,

I am writing a script for users to interact with that will present a few, well defined options for usage. For instance, they will have an option to telnet to a device, ssh to a device and telnet to several other core routers. All is well with the initial usage of the menu, when the user logs in he is presented with the menu and able to interact with it. However, the problem is when they telnet, ssh, etc. they are forked out of the menu and into whatever program they executed.
Is there a way to prevent this behavior? I was thinking that it might be best to write each function into its own shell script, therefore never leaving the initial menu. Any ideas would be appreciated.

The script so far:

Code:

#!/bin/sh
#set -x
user=`whoami`;
CLEAR=`which clear`;
TELNET=`which telnet`;
MENU=/usr/local/query/menu;
SSH=`which ssh`;

_Menu ()
{
        $CLEAR;
        echo " "
        echo "        ============================================================"
        echo "                                 NS2 MENU                           "
        echo "        ============================================================"
        echo "           1. Telnet to a Device          12. CMTS Intfc Modem Count"
        echo "           2. SSH to a Device             13. Ping/Traceroute Device"
        echo "           3. Clear SSH Known Hosts       14.  "
        echo "           4. Access Core1 GSR            15.  "
        echo "           5. Access Core2 GSR            16.  "
        echo "           6. Access Core3 VXR            17.  "
        echo "           7.                             18.  "
        echo "           8.                             19.  "
        echo "           9.                             20.  "
        echo "          10.                             21.  "
        echo "          11. Access Server             22.  "
        echo "        ============================================================"
        echo "                    Select a Menu Number Option      "or"           "
        echo "                 Type  H# for Help on a Menu Option  "or"           "
        echo "                        --Q  to Quit Menu--                         "
        echo "        ============================================================"
        echo -n "Enter Menu Option ======> "
        read option;

        case "$option" in

                1)
                        _telnet;
                ;;

                2)
                        _ssh;
                ;;

                3)
                        _clearssh;
                ;;

                4)
                        _core1;
                ;;

                5)
                        _core2;
                ;;

                6)
                        _core3;
                ;;

                11)
                        _aov;
                ;;

                12)
                        _mdmcnt;
                ;;

                13)
                        _pingtrace;
                ;;

                *)
                        $CLEAR;
                        echo -e "You chose an invalid response. Please try again.\n Press any key to continue.";
                        read junk;
                        $MENU
                ;;

                esac
}

_telnet ()
{
        $CLEAR;
        echo -n "Enter IP address of device and press Return: ";
        read host;
        $TELNET $host;
}
_ssh ()
{
        $CLEAR;
        echo -n "Enter IP address of deivce and press return: ";
        read host;
        $SSH $host
}

_clearssh ()
{
        $CLEAR;
        echo -e "Know hosts has been cleared.\n Press any key to continue.";
        read junk;
        $MENU;
}

_core1 ()
{
        $CLEAR
        $TELNET <someIP>

}
_core2 ()
{
        $CLEAR
        $TELNET <someIP>
}
_core3 ()
{
        $CLEAR
        $TELNET <someIP>
}
_Menu

0.o · 07-17-2008, 10:13 AM

I suppose one option would be to use the 'fork' command, eh?

0.o · 07-18-2008, 07:30 AM

No one have any suggestions?

unSpawn · 07-18-2008, 07:50 AM

Try "select"? Example: 'select selection in quit ssh telnet; do case $selection in quit) break;; ssh) ssh user@host;; *) echo $selection;; esac; done'

0.o · 07-18-2008, 08:49 AM

I don't think i was clear enough when i wrote the initial post.

When the user logs in, if they choose option 11, they can access the server through the script with no problem. However, when they are ready to leave the server they went to through the script, it exits out completely. i.e. They lose connection to the initial server as well as the one they initially connected to.

Is there anyway to stop this behavior? Why does it do this?

unSpawn · 07-18-2008, 10:05 AM

Scripts are traversed from start to finish, so if a) use replace the login shell with your menu and b) you're not keeping them in a continuous loop like my "select" example or point back to the main function inside a "child" function or follow a child function with calling _Menu, then the script will finish. Logging info from "set -x" debugging should show that.

mrmjolnir · 02-14-2013, 06:00 AM

Well, this answer comes after 5 years, but better late than never

Have you tried expect?
expect.sourceforge.net