Re: Can $1 be set in a script?

On Thu, 30 Mar 2006 23:15:35 -0900, floyd@xxxxxxxxxx (Floyd L.
Davidson) wrote:

larryalk <nobody@xxxxxxxxxxx> wrote:
On Fri, 31 Mar 2006 01:35:57 -0500, Bill Marcum <bmarcum@xxxxxxxxx>
wrote:

something=${1:-"default string"}

Excellent point.

Bill I ran across this exact same construction before in connection
with an ~/.xinitrc script.

Would you please tell me what the syntax means of:
(1:-"default string")

It does exactly the same thing that the several lines of my code
did.

I _guess_ it represents a variable.
What does the colon and minus sign signify?

Why guess... you should read the man page for bash...

Start by reading the section titled "Parameter Expansion".

Thank you Floyd. I had been thinking of how to use Google to get a
handle on that but man bash explained it all.

This {1:-string} construct is going to be very handy.

After re-thinking about my subject "Can $1 be set in a script?" I
realize that I just wasn't thinking. Apparently I made a big fuss
over nothing.

It's easy to create
1=something
2=borrowed

echo $1 $2
something borrowed

Voila, $1 and $2 created where they didn't exist before.
But {1:-string} is even better.

Larry

--
My real sig is much better.
.

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