Figuring out which shell?

daihard · 03-22-2006, 03:43 PM

Hi.

Is there a shell script command hat detects the type of shell it is run? I need to write a script that executes a certain command if the shell is, say, bash. It should look roughly like this:

Code:

#!/bin/sh
if [ /* shell is bash */ ]; then
    alias ch='source ${COMMAND_FOR_BASH};
else
    /* do something else */
fi

I need to fill in the part where the /* shell is bash */ comment is now. Would anyone be able to help me out here?

TIA,
Dai

daihard · 03-22-2006, 03:44 PM

Hi.

Is there a shell script command that detects the type of shell it is run in? I need to write a script that executes a certain command if the shell is, say, bash. It should look roughly like this:

Code:

#!/bin/sh
if [ /* shell is bash */ ]; then
    alias ch='source ${COMMAND_FOR_BASH};
else
    /* do something else */
fi

I need to fill in the part where the /* shell is bash */ comment is now. Would anyone be able to help me out here?

TIA,
Dai

daihard · 03-22-2006, 03:48 PM

Oops, this is a duplicate. I messed up the "submit" button. I asked the mods to delete this thread. If you have any feedback, please post it in the other thread with the same subject. Sorry for the inconvenience.

Dai

__J · 03-22-2006, 03:54 PM

# Set a default shell prompt:
#PS1='`hostname`:`pwd`# '
if [ "$SHELL" = "/bin/pdksh" ]; then
PS1='! $ '
elif [ "$SHELL" = "/bin/ksh" ]; then
PS1='! ${PWD/#$HOME/~}$ '
elif [ "$SHELL" = "/bin/zsh" ]; then
PS1='%n@%m:%~%# '
elif [ "$SHELL" = "/bin/ash" ]; then
PS1='$ '
else
PS1='\u@\h:\w\$ '

This is from the /etc/profile script on Slackware, try this and see if it works

daihard · 03-22-2006, 04:35 PM

Thanks, J! I took your advice and wrote it this way:

Code:

tmpshell=`echo $SHELL | awk -F/ '{ print $NF }'`
if [ "$tmpshell" == "bash" ]; then
    alias ch='source ${COMMAND_FOR_BASH}'
else
    /* do something else */
fi

Works great for me. Again, thanks for your quick response and useful information.

This must run on various UNIX/Linux flavours, such as Solaris, HP-UX, AIX, QNX-Neutrino, and RHEL. I hope I can safely assume that any such system has "awk" installed.

__J · 03-22-2006, 04:45 PM

Not sure if it will run on the other systems, slack only runs on a few architectures. Hopefully it works for you.

daihard · 03-22-2006, 05:13 PM

Quote:

Originally Posted by __J

Not sure if it will run on the other systems, slack only runs on a few architectures. Hopefully it works for you.

I tried it on all our UNIX systems, and it seems to work. Thanks again!

mikshaw · 03-22-2006, 08:25 PM

Not that it's seriously important, but you're running echo, awk, and if, when it can all be done inside a single case statement.

case $SHELL in
*bash) alias ch='source ${COMMAND_FOR_BASH}' ;;
*) whatever else ;;
esac

daihard · 03-22-2006, 08:47 PM

Quote:

Originally Posted by mikshaw

Not that it's seriously important, but you're running echo, awk, and if, when it can all be done inside a single case statement.

case $SHELL in
*bash) alias ch='source ${COMMAND_FOR_BASH}' ;;
*) whatever else ;;
esac

That is super cool! Thanks a lot for the advice. I learn something new every day here.