* * * * *
Too many emails
Email.
Or rather, an abundance of email.
Smirk called, saying that one of our servers was dying under a severe server
load, and asked if I could write a script to clean out the sendmail queues.
So I spent some time writing some Perl code to do just that.
I don't like Perl. To me, it represents the worst of /bin/sh, awk, sed and
grep (among other throat clearing noises that represent Unix commands). But
for one off stuff like this, it was probably quicker than trying to do this
purely under /bin/sh or even C.
In retrospect, I think I could have written it faster in C.
First off, I write my Perl using “strict”; it's enough that Perl will gladly
accept simple typos (unless in “strict” mode). But that lead to problem
number one: I couldn't figure out how to use Getopt::Std (Perl code to parse
the command line) in “strict” mode. I had to spend some time figuring out
that the correct incantation to use would be:
> use Getopt::Std;
> use strict;
>
> use vars qw($opt_h $opt_b $opt_d $opt_t $opt_D);
>
> getopts('h:b:d:t:D');
>
(in this code, -h is to scan the headers, -b to scan the body, -d to specify
the queue directory and -t to specify where any email matching should be
copied to, and -D to output debugging messages)
Okay, next problem: it's not finding anything. I grep through the headers,
find something like “Subject: AdD Thr33 IncHes 2 ur MOrtgAge” then run the
script:
> ./movequeue.pl -h 'Subject: .*[Mm][0Oo][Rr][Tt\?][Gg][Aa@][Gg][Ee3]' -D'
>
And nothing shows up.
Debug debug debug.
Turns out I'm a bit overzealous with using “my” (which is used to declare
which variables I'm using in “strict” mode). Each instance of “my $variable”
causes it create a whole new variable. So of course:
> foreach my $entry (@queue)
> {
> if (my $entry =~ /[dqx](.*)/)
> {
> # blah blah blah
> }
> }
>
isn't going to work, since I effectively get two new variables by the name of
$entry.
Okay, declare all the variables I use in one spot. That fixes that problem,
and a whole slew of other problems related to scoped variables.
But at least the code is working.
Why yes, I'm still learning Perl.
And I still don't like it.
Email author at
[email protected]
