On Tue, 17 Jul 2007 16:35:03 +0200, "Paul de Weerd"

said:

quoted text
> On Tue, Jul 17, 2007 at 03:27:51PM +0100, Stuart Henderson wrote:

> | > My manpage (ksh(1)) says :

> | >

> | >      [[ expression ]]

> | >              Similar to the test and [ ... ] commands (described

> later), with

> | >              the following exceptions:

> | >

> | > And then lists some exceptions. This could be a difference between sh

> | > and ksh (which, I believe, is only a difference in documentation).

> |

> | It does different things depending on whether it's run as ksh or sh.

>

> As far as my quick test (not definitive by any means) shows, it does

> not do anything different with respect to handling [[ ]].

>

> The description of [[ ]] is missing from sh(1) though, hence my

> statement "which, I believe, is only a difference in documentation".

[[ is not listed in sh(1) because this construct doesn't exist in sh(1).

There is a difference in the [[ construct in ksh. Read man ksh(1).

Most significantly;

o   Field splitting and file name generation are not per-

     formed on arguments.

o   The second operand of the `!=' and `=' expressions are

     patterns (e.g. the comparison [[ foobar = f*r ]] suc-

     ceeds).