Whats the difference between shells on Red Hat Linux 9.0!??
i see a lot of shells like:
- Screen Session
- Linux Console
- Shell
- Root Console

i don't know the diff and or what are they for..
any input appreciated!

thanx!

this is not definite answer
but just what i guess what the difference is

shell is a program that let u interact with os
example: bash/csh/tsch/zsh/sh

console is a type of interaction
command line based interaction opposed to GUI based

and shell and console are used interchangably

- Screen Session
- Linux Console
- Shell
- Root Console
don't worry about what u have to use, u can use any
just "root console" will log u on as root

My idea is that shells are command-line applications, in essence. They're what give you the prompt - or are the prompt, depending on how you want it. Whereas a console is your stdin/stdout - where the prompt appears - screen and keyboard. But neither one is any good without the other and they are used interchangeably. shell is bash and console is a tty. So I use the console to input and receive information from the shell, as it interacts with the OS. I dunno - just my impression.

There was some thread about console vs. terminal somewhere - there's another neat area of confusion.

But maybe you mean what's the difference between any shell or console relative to others? Never used anything but bash and have a tendency to go for xterm when I have a gui, while 'linux' is always the default console. I think it just has to do with the shells being coded differently and parsing commands differently so that some are better suited for certain tasks than others, while different gui terminal emulators have different bells and whistles like toolbars and menus and different responses to keys and pasting operations and whatnot.

But be fully prepared for my post to be 100% wrong when someone who actually knows comes along to clear things up.

Thats a bit of a hard one. All of the above use a shell. The shell is what gives you that pretty command line that's so friendly when you first use a linux box. A screen session sounds to me like it would apply to any kind of session on the Linux box in question, wethers its via a simply command line or via X. The linux console as you've put it is typically the primary display thats physically attached to the linux box - normally this is your monitor although some people use a simple serial-terminal as their console. A root console is just the console when you are logged in as root.

Does that make any sense?

Jamie...

hmmm... kind of... but still why would i want that many shells
if all they do the same! so wich one should i use for frequent
stuff!??

Shells are processes from which one may call other processes. That is, they are "command interpreters". They are an integral part of a unix system, and though one could get by without interactively using a shell, the typical system can't boot without some shell scripts.
A console is an interface to an interactive shell. I think your term, "Root Console" is an invention of the KDE and/or Gnome groups, it's basically a console with the interactive user of root. The same for "Linux Console", which is just a console run by the normal user that logged in to KDE.
A "screen session" is another name for an interactive shell running the program, "screen". Read the man page for screen, as it's a cool program if you have a need for managing multiple (interactive) processes on a single terminal. I have to admit that I don't know why KDE would put this in their menu, since it's mostly useful for non-X terminals.

They all do 'the same' very slightly differently, some shells are prefered for their syntax when writing scripts by some people, others prefer a different shell. It's all dependent on what you want to do. The Bourne Shell (plain /bin/sh) doesn't have many features but it almost standard accross the Unix world so a shell script written using sh should work on just about any system. Where as the C Shell (csh / tcsh) uses a more C like syntax that people who code in C prefer, although it may not be present on all systems.
I tend to use Bash (the Bourne Again SHell) for most of my stuff but its all a matter of preference.

cheers

Jamie...

A screen session is most likely a bash prompt run inside the screen VT multiplexor program, man screen will tell you more about this very useful (for people like me) program.