topic Re: default shell in Operating System - HP-UX

default shell

Shivkumar — Sun, 14 Aug 2005 23:30:15 GMT

I guess hpux uses posix shell as a defualt. what is the difference between posix and bourne shell ?

What is the command to verify defualt shell ?

Thanks,
Shiv

Re: default shell

Yogeeraj_1 — Sun, 14 Aug 2005 23:38:56 GMT

hi,

for more information on the different shell, do "man sh"

to futher drill down on the man pages, try:
man sh-bourne #Bourne Shell (/usr/old/bin/sh) description.
man ksh #Korn Shell (/usr/bin/ksh) description.
man sh-posix #POSIX Shell (/usr/bin/sh) description.
man csh #C Shell (/usr/bin/csh) description.
man keysh #Key Shell (/usr/bin/keysh) description.

to verify the default shell,
do:
echo $SHELL

hope this helps too!

regards
yogeeraj

Re: default shell

Yogeeraj_1 — Sun, 14 Aug 2005 23:44:03 GMT

hi again,

note that the default shell in hp-ux is the POSIX shell. Note that the Bourne shell is a subset of the default HP-UX shell.

read more on page 466 on marty's book!

regards
yogeeraj

Re: default shell

Joseph Loo — Sun, 14 Aug 2005 23:54:47 GMT

hi shiv,

to verify shell:

# echo $SHELL
or
# cat /etc/passwd
the last parameter for each user

regards.

Re: default shell

Joseph Loo — Sun, 14 Aug 2005 23:56:21 GMT

hi shiv,

forgot the first part of your questions, here goes:

http://docs.hp.com/en/B2355-90046/ch15s03.html

http://docs.hp.com/en/B2355-90164/ch03s04.html

regards.

Re: default shell

Indira Aramandla — Mon, 15 Aug 2005 00:29:42 GMT

Hi Shiv,

You can ehco the shell when you logged on as a user to fing the default shell

by
echo $SHELL

or the password file /etc/passwd has a record of the username, user-id, user group, home directory and the default shell for the user.

IA

Re: default shell

Cem Tugrul — Mon, 15 Aug 2005 02:39:54 GMT

Shiv,

echo $SHELL
may show what you actually running shell;
also for to understand your users running
shell;
cat /etc/passwd|grep -i userid or username

Good Luck,

Re: default shell

Bill Hassell — Mon, 15 Aug 2005 07:58:32 GMT

The Bourne shell has been deprecated (not recommended) for at more than a decade, and in HP-UX, it is hidden in the directory /usr/old/bin/. Unfortunately, HP chose the name sh for it's POSIX shell so newcomers to HP-UX will assume that if the shell is sh, then it muist be the Bourne shell. You can easily test whether the shell is Bourne by typing something like this:

export x=1

In Bourne, the produces the error:

x=1: is not an identifier

but for POSIX shells, the command works just fine. Notice I said "POSIX shells"? POSIX is a standards organization and you can read more about it at http://www.posix.com/posix.html

The Korn shell is the model for POSIX standard so the Korn shell, BASH and HP's POSIX shell are all POSIX-compliant shells which means that they are virtually identical. Most of the differences are in user profiles, specialized user interfaces such as defining non-ASCII keys (like arrow keys), and command line recall/editing options.

So if you're familiar with Korn or BASH, there is virtually no difference between the shells. NOTE: in HP-UX, the root shell *MUST* be /sbin/sh. The /sbin directory is the special purpose directory used for bootup and single user mode. All commands in /sbin have been compiled to not require the /usr/lib directory (which is not present in single user mode).