unix command line arguments

[Fonzie]

If I have a unix script and I send it the following command line argument:

a3 c makemoneyfa$t

I am returned with the message:

t: Undefined variable

I know this is because the '$' symbol is special, but I was wondering if there was some kind of work around for this. I know I could give the command line:

a3 c makemoneyfa\$t

but I was wondering if there's something I could put inside my program itself, rather than the command line, that could defend against special characters in command line arguments.

[wtd]

That is the workaround.

[Fonzie]

but that's something the user would be doing when trying to use the program. Is there nothing I can do so that the user can have special characters in their filename and my script be able to handle it?

[wtd]

I think you may be confused by the order of evaluation.

Let's say we really do have a variable t.

code:

t=foo

Now, we try to call:

code:

bar baz$t

The "bar" program does not see "baz$t" as its first argument and then magically turn that into "bazfoo".

Rather, the shell turns "baz$t" into "bazfoo" and then sends that to "bar".

[Fonzie]

thankyou, I think I understand. I'm curious though, is there a difference between these two lines?

a3 c 'makemoneyfa$t'
a3 c makemoneyfa\$t

[wtd]

Effectively, no.

Single quoted strings do not undergo variable interpolation.