@
variable
=
expression
@
variable
[
n
] =
expression
@
Assign the value of the arithmetic
expression
to
variable
,
or to the
n
th element of
variable
if the index
n
is specified. With no
variable
or
expression
specified, print the values of all shell variables (same as
set
).
Expression operators as well as examples are listed under "Expressions,"
earlier in this section. Two special forms are also valid:

@
variable
++ Increment
variable
by one.


@
variable
  Decrement
variable
by one.
