03-14-2012
I'd consider trap safer because it can eat a SIGINT from any source -- kill and the like -- not just those that come from the keyboard. Besides, who's to say you don't want the program to do something on ctrl-c?
The main advantage of changing their login shell to your script is that, if they manage to kill it somehow, all they accomplish is logging themselves out. There's no interactive shell behind your application to "break out" into. Disadvantage is that it can be harder to arrange. Some systems need you to add your application to /etc/shells before they'll let people use it as their 'shell'.
I'm sure there's general-purpose menu systems. Of course, just because something's compiled doesn't mean it doesn't have holes -- it just makes it harder to know whether it has holes...
This User Gave Thanks to Corona688 For This Post:
10 More Discussions You Might Find Interesting
1. Homework & Coursework Questions
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
1) Write a Menu Driven Shell Script which accepts1 to 5 options and performs the following actions for... (1 Reply)
Discussion started by: vaghya
1 Replies
2. Shell Programming and Scripting
How do I assign values to reference variables?
I am assigning a variable name to --> $user_var
Then I am trying to change its underlying variable value by
$((user_var))=$user_value .. its failing,,
Please let me know if there is a way to do this dynamically..
FileA.props... (5 Replies)
Discussion started by: kchinnam
5 Replies
3. Shell Programming and Scripting
Hi Guys..
am new to unix scrpiting..I need a Menu need to create using shell scrpting
eg:
Food items
ready
paid
if i press "f" need to add items for a file food items..
if i press "r" it need to move into ready and remove from food items
if i press "p" need to update a filed in... (1 Reply)
Discussion started by: sasdua
1 Replies
4. SuSE
QUESTION:
Write shell script using menu-driven approach to show various system configuration like
1) Currently logged user and his logname
2) Your current shell
3) Your home directory
4) Your current path setting
5) Your current working directory
6) Show Currently logged number of... (1 Reply)
Discussion started by: bboyjervis
1 Replies
5. UNIX for Dummies Questions & Answers
i'm confused what this means.
i was asked to design a menu or command line option driven script that reads out of a DB and displays info such as
read_data.pl -u <user> -e <event>
which would print commands run by <user>with the <event> in the db.
any suggestions? i've been using... (2 Replies)
Discussion started by: kpddong
2 Replies
6. Shell Programming and Scripting
Hi, I was wondering if someone could help me write a shell script in Linux that backsup/restores data to anywhere I choose but it needs to be menu driven?
Thanks, I'm new to Linux/Unix but liking it so far...just hoping to get to grips with the scripts! :) (7 Replies)
Discussion started by: Nicole
7 Replies
7. Shell Programming and Scripting
I'm a beginner at scripting and have been putting this script together over the past week. It's no where as polish as it could be. Any tips/suggestions on improving this script would be appreciate it. Every week, my team develops WAR files in tomcat on our test environment and moves them to our... (4 Replies)
Discussion started by: bouncer
4 Replies
8. Shell Programming and Scripting
HI All..
below is my menu options script. in option 2,3 and 4 im giving input and they are saving into their respective text file.
problem is when im trying to "cat" those files in options 7,8 and 9 im not getting the output. no respective file contents are displaying on screen. but if i... (1 Reply)
Discussion started by: saichand1985
1 Replies
9. Shell Programming and Scripting
Hi All,
I have written a menu driven bash shell script.
Current Output is as below:
-------------------------------------
Main Menu
-------------------------------------
Option 1
Option 2
Option 3
Option 4
Exit
=====================================
Enter your... (3 Replies)
Discussion started by: kiran_j
3 Replies
10. Shell Programming and Scripting
Hi Team ,
I wrote a shell script for adding and subtracting two numbers am getting error could some one please help to fix it
script:
echo "Enter 1 to add:"
echo "Enter 2 to sub:"
echo "Enter 3 for both addition and subtraction :"
read ans;
case "$ans" in
1)... (4 Replies)
Discussion started by: knz
4 Replies
sh(1) General Commands Manual sh(1)
NAME
sh - overview of various system shells
SYNOPSIS
POSIX Shell
option] ... string] [arg ...]
option] ... string] [arg ...]
Korn Shell
option] ... string] [arg ...]
option] ... string] [arg ...]
C Shell
[command_file] [argument_list ...]
Key Shell
DESCRIPTION
Remarks
The POSIX .2 standard requires that, on a POSIX-compliant system, executing the command activates the POSIX shell (located in file on HP-UX
systems), and executing the command produces an on-line manual entry that displays the syntax of the POSIX shell command-line.
However, the command has historically been associated with the conventional Bourne shell, which could confuse some users. To meet stan-
dards requirements and also clarify the relationships of the various shells and where they reside on the system, this entry provides com-
mand-line syntax and a brief description of each shell, and lists the names of the manual entries where each shell is described in greater
detail.
The Bourne shell is removed from the system starting with HP-UX 11i Version 1.5. Please use the POSIX shell as an alternative.
Shell Descriptions
The HP-UX operating system supports the following shells:
POSIX-conforming command programming language and command interpreter
residing in file Can execute commands read from a terminal or a file. This shell conforms to current POSIX standards in
effect at the time the HP-UX system release was introduced, and is similar to the Korn shell in many respects. Similar in
many respects to the Korn shell, the POSIX shell contains a history mechanism, supports job control, and provides various
other useful features.
Korn-shell command programming language and commands interpreter
residing in file Can execute commands read from a terminal or a file. This shell, like the POSIX shell, contains a his-
tory mechanism, supports job control, and provides various other useful features.
A command language interpreter
that incorporates a command history buffer, C-language-like syntax, and job control facilities.
Restricted version of the POSIX shell command interpreter.
Sets up a login name and execution environment whose capabilities are more controlled (restricted) than normal user
shells.
restricted version of the Korn-shell command interpreter
Sets up a login name and execution environment whose capabilities are more controlled (restricted) than normal user
shells.
An extension of the standard Korn Shell
that uses hierarchical softkey menus and context-sensitive help.
+--------------+--------------------+
| To obtain: | Use the command: |
+--------------+--------------------+
| POSIX Shell | /usr/bin/sh ... |
| Korn Shell | /usr/bin/ksh ... |
| C Shell | /usr/bin/csh ... |
| Key Shell | /usr/bin/keysh |
+--------------+--------------------+
These shells can also be the default invocation, depending on the entry in the file. See also chsh(1).
WARNINGS
Many manual entries contain descriptions of shell behavior or describe program or application behavior similar to ``the shell'' with a ref-
erence to ``see sh(1)''.
SEE ALSO
For more information on the various individual shells, see:
keysh(1) Key Shell description.
ksh(1) Korn Shell description.
sh-posix(1) POSIX Shell description.
csh(1) C Shell description.
sh(1)