On Mon, May 10, 2004 at 08:56:24PM -0400, Chad Perrin wrote:
<snip>
> I take it, then, that anything inside quotes is typically interpreted by
> the shell, and the quotes only serve to group elements of a statement
> together.
In general, yes.
That's true for double-quotes, but not for single-quotes. That is:
something "$ANYTHING"
would fetch the value for the variable ANYTHING and insert that into the
quoted string. But
something '$ANYTHING'
would assume that $ANYTHING is a string literal. Backticks (`) behave
similarly to double-quotes, but execute what lies inside the
backtick-quoted string. This is usually used in assigning variables, as:
DATE=date
NOW=`$DATE +%Y-%m-%d`
would yield:
2004-05-11
An alternate way to execute something (besides backticks) is:
NOW=$($DATE +%Y-%m-%d)
And you can do integer math by using double parentheses:
$ SUM=$((3 + 2))
$ echo $SUM
$ 5
(More than you wanted to know, right?) ;-}
Paul
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