Re: Ping an ip address range

Janis Papanagnou wrote:

On 26.05.2011 12:51, Radoulov, Dimitre wrote:
On 26/05/2011 09:12, Janis Papanagnou wrote:

Is $(( k += 1 )) meanwhile standard? I thought that would be

k=$(( $k + 1 ))

If I read it correctly, now it *is* standard:

If the shell variable x contains a value that forms a valid integer constant,
then the arithmetic expansions "$((x))" and "$(($x))" shall return the same
value.

That's one aspect; x vs. $x inside $((...)). Another one, IIRC, had been
(un-)availability of operator += and (I think) also the assignment within
the $((...)) vs. outside. (I may be misremembering, though.)

The += and other assignment operators have always been mandated by
POSIX. What wasn't clear in older revisions of the standard was
whether an assignment to a shell variable inside an arithmetic
expansion has to be reflected in the value of the variable after the
expansion. I quoted the new text that clarifies this in my other post
in this thread.

--
Geoff Clare <netnews@xxxxxxxxxxxxx>

.

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