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paulm (5067)

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Hello! I'm Paul Makepeace [], a regular on []. Perl's my primary language I code in (since '95 I think); people even pay me [] for it! Although I'd say I'm a developer I spend a substantial chunk of time being a sysadmin for my own machines (I'm also one of's root), all Debian boxen.

This journal is my first foray into a technical annotation of my perl life...

Journal of paulm (5067)

Monday February 14, 2005
11:22 AM

25 hours in a day

sub days_between($$) {
    (str2time($_[1])-str2time($_[0])) / SECONDS_IN_A_DAY;

Seems obvious enough. Then some results were non-integer. Boiled down to,

$ perl -MDate::Parse -le 'print ((str2time($ARGV[1])-str2time($ARGV[0]))/86400)' 2004-10-31  2004-11-01

Why? Ah, Daylight savings!

Monday January 10, 2005
11:00 PM

Binary reflex

Dave Gould says:
    6 OR 7?
paulm says:
Dave Gould says:
    scuse caps lock
paulm says:
    oh, in that case I don't know

Thursday October 14, 2004
05:01 AM

Mailman wrapper

Mailman has this concept of a URL that's associated with a domain. Unfortunately it's not possible to configure it through the interface, which on vhosted lists is really annoying. There is an impossible-to-remember incantation with an auxilliary script. Tired of looking this up and messing up the invocation here's a wrapper. Yeah, it's in perl.


use strict;
use warnings;

# paulm, 2004-10-14
# Provide a pleasant interface to mailman's script

my ($program) = $0 =~ m~.*/(.+)$~;
sub usage { die "$program: $program list\\n@_.\n" }
usage("Missing list address")
        unless @ARGV == 1;
my ($local_part, $domain) = split '@', $ARGV[0];
usage ("Couldn't parse $ARGV[0] into a list address")
        unless $local_part and $domain;
print "Fixing ${local_part}\@$domain...\n";
system qq{/usr/lib/mailman/bin/withlist -l -r fix_url $local_part -u $domain};

Friday June 11, 2004
10:12 AM

Windows NT, VMS?

(Lifted from, this thread on Windows NT v. VMS).

Je 2004-06-11 00:20:29 +0100, Phil Lanch skribis:
> On Wed, Jun 09, 2004 at 02:50:35PM +0100, David Cantrell wrote:
> > I would be *much* happier running the bastard child of VMS
> hang on a minute ... isn't Windows NT the bastard child of VMS?
$ perl -pe 's/(.)/chr -1+ord $1/ge'

Try "IBM" too :-)

Tuesday June 08, 2004
07:32 PM

Stripping certain requests from log files

I have this service that performs a HEAD request on a few sites I run, every few minutes. The problem is that it inflates my page hit count. Being one of those problems that is too annoying to do properly, the following one-liner (line broken for a shot at clarity) came out surprisingly easily,

for i in*gz; do
  gunzip $i; f=`echo $i | perl -pe 's/.gz//'`;
  perl -ni -e 'print unless /^ftp.itransact/' $f;
  gzip $f& echo $f;

Friday May 28, 2004
09:36 AM


A "zero script" hack (-e0) to convert in-place Macs' default line endings of \r to \n.

perl -le0 -015pi mac_file.txt

The order of the -l and -0 is important. -l assigns $\=$/ (output record sep = input record sep) and then the -015 sets input record separator to octal 15, aka dec 13 aka \r. So it's splitting the input on \r and outputting (via -p) with \n.

(I was puzzled for a while trying to squeeze even more characters out of it by wondering why -l0 was behaving differently to -l -0. -l takes a number too! So the 0 was a number not a command option.)

Can any more chars be shaved off?

Saturday May 22, 2004
12:36 PM

First post!

I've recently really enjoyed reading the journals on use Perl (in particular Matts's and davorg's I'm sure I'll discover more!) and combined with a feeling I ought to spend time documenting what I get up to with perlif only so I remember in a week's timeit seemed a natural step to join up.

If you know me (heck, even if you don't :) please do say hi! Any use Perl tips gratefully received too (an overwhelming number of cool-looking doodads here...).