On Tue, 7 Dec 2004 13:54:41 -0500, Ed Christian <[EMAIL PROTECTED]> wrote:
> [SNIP]
> I'm certainly far from a Perl expert, but one suggestion I do have is to
> be careful to test that your regular expression does have a match before
> using $1. I believe $1 contains the first match from the last
> _successful_ regex, not just the last regex. I would change the above
> snippit to something along the lines of:
>
> my $ppp0 = `/sbin/ifconfig ppp0`;
> die "Invalid output from ifconfig! Received: $ppp0\n"
> unless ($ppp0 =~ m/(\d+\.\d+\.\d+\.\d+)/);
> my $ip = $1;
I agree strongly here, because robustness is required in this instance.
Never rely on a PPP connection being up when coding...
Stylistically, I would prefer C<if> here (SUGGESTION ONLY):
if ($ppp0 =~ m/(\d+\.\d+\.\d+\.\d+)/) {
# Success, work with $1 etc.
}
else {
die "Invalid output from ifconfig! Received: $ppp0\n"
}
Reason: By using a postfix conditional, you are placing emphasis on the
error message not the condition that follows it. I wouldn't normally expect
a postfix conditional to also have important side effects. You may not
agree.
Jonathan Paton
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