Say I have an executable shell script called "foo"...

and then I alias to it like so:

alias bar foo

so now if I run "foo" or "bar", the same shell script runs.

Is there a way, in the shell script, that I can tell if I was called as "foo" or "bar"? In tcsh, I was checking $0, but that always seems to be "foo" even if I ran it as "bar". I don't care if it's tcsh or bash or even a python script (preferably not perl or anything that can't be interpreted on the fly, like compiled C).

no,
the shell converts it before it runs

That's unfortunate.

Back to the drawing board.

can you tell us your intentions
i understand if you cant but it would help solve the problem

If you create a *link* 'bar' to 'foo', then when you run it, it can know it was called as 'bar' or 'foo' -at least in sh/bash. This method is used for rc.0/rc.6 shutdown items -rc.0 is a link to rc.6. The called name tells the script what to do(this is under Slackware -YMMV).

but the original poster said alias not symlink

not sure if it fits ur purpose....i tried this ,


<$>vi test.skh
"test.skh" [New file]
echo "running $0 "
:wq!


first run:test.skh
<$>./test.skh
running ./test.skh

second run:test.ksh
<$>ln -s test.skh test.ksh
<$>test.ksh
running ./test.ksh
<$>ln -s test.skh test1.ksh
3rd Run:
<$>test1.ksh
running ./test1.ksh

got it?

yes,i pasted o/p for all my 3 runs...

sorry for the outbusrt
i was trying to say the original poster is talking about alias not ln

The OP said: "Back to the drawing board", so the suggestion about using links is a way to implement what he seemed to be trying to do -differentiate between the way a single script 'identifies' itself.

Hello all,

After I replied, I remember that I had previously done this via symlinks as you suggested. That doesn't work in this particular case, however.

For the record, I'm writing a controller for a slew of applications - groups of which need their own, unique PATHs (and a few other env vars). Rather than polluting each user's env with a ton of potentially conflicting paths, the controller is setting paths on the fly, then launching the application. When the app closes, all env vars go back to what they were before.
The purpose of the alias is to send all the potential application executables through the controller script. Being that the aliases, themselves, are created on the fly, I've simply appended some extra info to each alias, i.e. "--prog_group foo --app_name bar". Problem solved.

Thanks for all the suggestions.