John W. Krahn wrote:
> pa...@compugenic.com wrote:
>> I want to extract a list of postfix's queue id's. The 'mailq' command
>> returns output as follows:
>>
>> --
>> 8C0597408D 2503 Tue Feb 17 16:15:34 ka...@domain.org
>> (connect to bar-plate.com[209.62.20.192]:25: Connection refused)
>> staffo...@bar-plate.com
>>
>> 88E8E7409E 1881 Tue Feb 17 23:37:40 dia...@domain.org
>> (connect to mail.fbig.com[70.68.160.253]:25: Connection timed out)
>> persistencer5...@fbig.com
>> --
>>
>> right now I'm doing the following:
>>
>> my @ids;
>>
>> foreach (`mailq`) {
>> next unless /^\w+/;
>> chomp;
>> push @ids, (split)[0];
>> }
>>
>>
>> I know it can be done with one line. Here's what I've got so far:
>>
>> my @ids = map {chomp; (split)[0] if /^\w/} `mailq`;
>
> You don't need chomp() because split() removes *all* whitespace, and
> besides you are only using the first field.
>
>
>> This 'kinda' works, but it also adds a bunch of blank elements to the
>> @ids array. What am I doing wrong?
>
>
> my @ids = map /^\w/ ? (split)[0] : (), `mailq`;
my @ids = map /^(\w+)/, `mailq`;
Rob
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