Changing shells in Terminal

Hi All,

I have Terminal 2.2.1. It appears that I cannot change from bash shell to tsch on the fly. I find this rather surprising:

>$ echo $SHELL
/bin/bash
>$ /bin/tcsh
>% echo $SHELL
/bin/bash

Can anyone explain this behavior to me?

Thanks,
Will

mikeMBP:~ mike$ echo $SHELL
/bin/bash
mikeMBP:~ mike$ echo $0
-bash
mikeMBP:~ mike$ exec /bin/tcsh
[mikeMBP:~] mike% echo $0
/bin/tcsh
[mikeMBP:~] mike% echo $SHELL
/bin/bash
[mikeMBP:~] mike%

Note that after the exec, the prompt changed (and it did in your example too)? The change from $ to %? That's a dead giveaway. $ is a bash shell prompt, % is a c shell prompt. $SHELL still echos /bin/bash though.

A better example is this. The print command does not exist in bash, but exists in korn.

mikeMBP:~ mike$ print "korn shell"
-bash: print: command not found
mikeMBP:~ mike$ exec /bin/ksh
$ print "korn shell"
korn shell
$ Echo $0
/bin/ksh
$ foo
/bin/ksh: foo: not found
$ echo $SHELL
/bin/bash
$

if we take a look at the environment variables... we see that SHELL is defined as /bin/bash. You'd have to export a new variable to change that.

mikeMBP:etc mike$ env
TERM_PROGRAM=Apple_Terminal
TERM=xterm-256color
SHELL=/bin/bash
CLICOLOR=1

will.flanagan said:

I have Terminal 2.2.1. It appears that I cannot change from bash shell to tsch on the fly.

Click to expand...

As Mike noted, you did change shells but note that the env. variable doesn't change with it. If you want to change that at the same time, you can execute the following: You have to export the new value first as noted in the command above. Otherwise, it won't take since tcsh will have already launched.

You'll note here that when you do this, the value of $SHELL remains /bin/tcsh when you exit tcsh so you'll have to export /bin/bash if you want $SHELL to change back.

Thanks

Thanks vansmith and Dysfunction!

The $SHELL variable not changing is strange to my linux background, but I appreciate the help

Will

This behaviors identical on the linux boxes I work on. Might be a distribution thing though.