One woman can’t have a baby in nine months


Originally posted on A billion monkeys can't be wrong:

As all software developers know, nine women can’t have a baby in a month. Or in Fred Brooks’s more elegant phrasing: “The bearing of a child takes nine months, no matter how many women are assigned.” (The Mythical Man Month, p. 17) The point, of course, is that some tasks are, as Brooks would say, “sequentially constrained”. They’re going to take a certain amount of time no matter what — the time can’t be reduced by having more people work on them.

On the other hand, is it actually the case that one woman can have a baby in nine months? Suppose we have just been put in charge of Project New Baby that must produce a brand new baby in nine months. How should we staff the project. Easy enough — nine women can’t have a baby in a month, right? No point in overstaffing so we’ve…

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TeX fonts for the Web


I love the fonts that come out of LaTeX. However I’ve never seen sites displayed using the same fonts, so I wanted to find if it was available to put on a website.

TLDR; It looks like you can get a very close free font called Latin Modern Roman.

Self help

This meant a bit of self education to see if I could get the fonts on the web. Donald Knuth created a program Metafont to create the font which is called Computer Modern and is part of the AMS Type-1 fonts. However there doesn’t appear to be any direct web fonts (i.e. .eot + .otf + .woff + .svg) files for Computer Modern. The best I found was the Unicode otf font that you can download for windows.

Latin Modern

However one ‘Computer Modern woff’ search did bring up a monotype font Latin Modern Mono, which has in its notes:

The Latin Modern fonts are derived from the famous Computer Modern fonts designed by Donald E. Knuth and first published by the American Matematical Society (AMS) in 1997. One of the main extensions is the addition of an extensive set of diacritical characters, covering many scripts based on the Latin character set, mainly european, but not only, most notably Vietnamese.

Then its a short hop to the actual serif font (which doesn’t have those helpful notes, so you don’t find it on the internet). So I give you Latin Modern Roman the Computer Modern font for the web.


Of course now that I’ve found it, I’ve acutally spotted that there was a link in one of the first places I found, the wonderous stack exchange: . I’d just followed the first Unicode link instead of reading further.

Mini Plesk – VirtualHosts in Apache


There is Apache Documentation for setting up Virtual Hosts, good luck if you can implement something sensible direct from that, but otherwise read on.

After umming and ahhing I finally decided to get some proper virtual hosts set up on a webserver of mine. This was brought on by creating a virtual host for a separate domain that completely overtook the default domain even though I didn’t think it should.

I also noticed that there is a sites-available and a sites-enabled directory in the /etc/apache2 directory. So a quick Google search brought up Hosting multiple websites with Apache2.

I followed this guide except for:

  1. using an extra vhosts directoryi.e. /var/www/vhosts (to agree with plesk)
  2. calling the htdocs directory httpdocs e.g. /var/www/vhosts/ (again to agree with plesk)
  3. logs directory should be put in /var/www/vhosts/ rather than /var/www/vhosts/
  4. To fix a bug I hit (see Trouble Shooting below), I used *:80 in the VirtualHost tag

Here is my file:

# (/etc/apache2/sites-available/
# @link
<VirtualHost *:80>

  # Indexes + Directory Root.
  DirectoryIndex index.php
  DocumentRoot /var/www/vhosts/
  Options FollowSymLinks

  # CGI Directory
  ScriptAlias /cgi-bin/ /var/www/vhosts/
  <Location /cgi-bin>
    Options +ExecCGI

  # Logfiles
  ErrorLog  /var/www/vhosts/
  CustomLog /var/www/vhosts/ combined

Trouble shooting

I kept getting the following error after following the guide:

NameVirtualHost *:80 has no VirtualHosts

Took me a while to figure out the problem, but I eventually tracked it down to the fact that there is already a NameVirtualHost defined in /etc/apache2/ports.conf and I had disabled the default site which was the only virtual host defined on *:80. The article wants you to create another file with this directive for * and then only include * for all virtual host definitions.

The Apache documentation is quite scathing about using just *:

To receive requests on all interfaces, you can use an argument of *:80, or, if you are listening on multiple ports and really want the server to respond on all of them with a particular set of virtual hosts, *

So I then did the following:

  1. Commented out all code in the conf.d/vhosts.conf file as its not required
  2. Put *:80 (not *) in all the VirtualHost definitions for the sites in sites-available


The above article doesn’t explain about setting up SSL/HTTPS domains. I think from Plesk 10 onwards both http and https used the httpdocs directory by default, so we just need to copy the existing file and copy it to and then merge in some details from the default-ssl file.

I followed this How To Set Up An SSL Vhost Under Apache2 On Ubuntu article and I ended up with the following config file:

# (/etc/apache2/sites-available/
# @link
<IfModule mod_ssl.c>
<VirtualHost *:443>

  # Indexes + Directory Root.
  DirectoryIndex index.php
  DocumentRoot /var/www/vhosts/
  Options FollowSymLinks

  # CGI Directory
  ScriptAlias /cgi-bin/ /var/www/vhosts/
  <Location /cgi-bin>
    Options +ExecCGI

  # Logfiles
  ErrorLog  /var/www/vhosts/
  CustomLog /var/www/vhosts/ combined

  #   SSL Engine Switch:
  #   Enable/Disable SSL for this virtual host.
  SSLEngine on

  #   A self-signed (snakeoil) certificate can be created by installing
  #   the ssl-cert package. See
  #   /usr/share/doc/apache2.2-common/README.Debian.gz for more info.
  #   If both key and certificate are stored in the same file, only the
  #   SSLCertificateFile directive is needed.
  SSLCertificateFile    /etc/ssl/certs/
  SSLCertificateKeyFile /etc/ssl/private/

  #   Server Certificate Chain:
  #   Point SSLCertificateChainFile at a file containing the
  #   concatenation of PEM encoded CA certificates which form the
  #   certificate chain for the server certificate. Alternatively
  #   the referenced file can be the same as SSLCertificateFile
  #   when the CA certificates are directly appended to the server
  #   certificate for convinience.
  #SSLCertificateChainFile /etc/apache2/ssl.crt/server-ca.crt

  #   Certificate Authority (CA):
  #   Set the CA certificate verification path where to find CA
  #   certificates for client authentication or alternatively one
  #   huge file containing all of them (file must be PEM encoded)
  #   Note: Inside SSLCACertificatePath you need hash symlinks
  #         to point to the certificate files. Use the provided
  #         Makefile to update the hash symlinks after changes.
  #SSLCACertificatePath /etc/ssl/certs/
  #SSLCACertificateFile /etc/apache2/ssl.crt/ca-bundle.crt

  #   Certificate Revocation Lists (CRL):
  #   Set the CA revocation path where to find CA CRLs for client
  #   authentication or alternatively one huge file containing all
  #   of them (file must be PEM encoded)
  #   Note: Inside SSLCARevocationPath you need hash symlinks
  #         to point to the certificate files. Use the provided
  #         Makefile to update the hash symlinks after changes.
  #SSLCARevocationPath /etc/apache2/ssl.crl/
  #SSLCARevocationFile /etc/apache2/ssl.crl/ca-bundle.crl

  #   Client Authentication (Type):
  #   Client certificate verification type and depth.  Types are
  #   none, optional, require and optional_no_ca.  Depth is a
  #   number which specifies how deeply to verify the certificate
  #   issuer chain before deciding the certificate is not valid.
  #SSLVerifyClient require
  #SSLVerifyDepth  10

  #   Access Control:
  #   With SSLRequire you can do per-directory access control based
  #   on arbitrary complex boolean expressions containing server
  #   variable checks and other lookup directives.  The syntax is a
  #   mixture between C and Perl.  See the mod_ssl documentation
  #   for more details.
  #<Location />
  #SSLRequire (    %{SSL_CIPHER} !~ m/^(EXP|NULL)/ \
  #            and %{SSL_CLIENT_S_DN_O} eq "Snake Oil, Ltd." \
  #            and %{SSL_CLIENT_S_DN_OU} in {"Staff", "CA", "Dev"} \
  #            and %{TIME_WDAY} >= 1 and %{TIME_WDAY} <= 5 \
  #            and %{TIME_HOUR} >= 8 and %{TIME_HOUR} <= 20       ) \
  #           or %{REMOTE_ADDR} =~ m/^192\.76\.162\.[0-9]+$/

  #   SSL Engine Options:
  #   Set various options for the SSL engine.
  #   o FakeBasicAuth:
  #     Translate the client X.509 into a Basic Authorisation.  This means that
  #     the standard Auth/DBMAuth methods can be used for access control.  The
  #     user name is the `one line' version of the client's X.509 certificate.
  #     Note that no password is obtained from the user. Every entry in the user
  #     file needs this password: `xxj31ZMTZzkVA'.
  #   o ExportCertData:
  #     This exports two additional environment variables: SSL_CLIENT_CERT and
  #     SSL_SERVER_CERT. These contain the PEM-encoded certificates of the
  #     server (always existing) and the client (only existing when client
  #     authentication is used). This can be used to import the certificates
  #     into CGI scripts.
  #   o StdEnvVars:
  #     This exports the standard SSL/TLS related `SSL_*' environment variables.
  #     Per default this exportation is switched off for performance reasons,
  #     because the extraction step is an expensive operation and is usually
  #     useless for serving static content. So one usually enables the
  #     exportation for CGI and SSI requests only.
  #   o StrictRequire:
  #     This denies access when "SSLRequireSSL" or "SSLRequire" applied even
  #     under a "Satisfy any" situation, i.e. when it applies access is denied
  #     and no other module can change it.
  #   o OptRenegotiate:
  #     This enables optimized SSL connection renegotiation handling when SSL
  #     directives are used in per-directory context.
  #SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire
  <FilesMatch "\.(cgi|shtml|phtml|php)$">
    SSLOptions +StdEnvVars
  <Directory /cgi-bin>
    SSLOptions +StdEnvVars

  #   SSL Protocol Adjustments:
  #   The safe and default but still SSL/TLS standard compliant shutdown
  #   approach is that mod_ssl sends the close notify alert but doesn't wait for
  #   the close notify alert from client. When you need a different shutdown
  #   approach you can use one of the following variables:
  #   o ssl-unclean-shutdown:
  #     This forces an unclean shutdown when the connection is closed, i.e. no
  #     SSL close notify alert is send or allowed to received.  This violates
  #     the SSL/TLS standard but is needed for some brain-dead browsers. Use
  #     this when you receive I/O errors because of the standard approach where
  #     mod_ssl sends the close notify alert.
  #   o ssl-accurate-shutdown:
  #     This forces an accurate shutdown when the connection is closed, i.e. a
  #     SSL close notify alert is send and mod_ssl waits for the close notify
  #     alert of the client. This is 100% SSL/TLS standard compliant, but in
  #     practice often causes hanging connections with brain-dead browsers. Use
  #     this only for browsers where you know that their SSL implementation
  #     works correctly.
  #   Notice: Most problems of broken clients are also related to the HTTP
  #   keep-alive facility, so you usually additionally want to disable
  #   keep-alive for those clients, too. Use variable "nokeepalive" for this.
  #   Similarly, one has to force some clients to use HTTP/1.0 to workaround
  #   their broken HTTP/1.1 implementation. Use variables "downgrade-1.0" and
  #   "force-response-1.0" for this.
  BrowserMatch "MSIE [2-6]" \
        nokeepalive ssl-unclean-shutdown \
        downgrade-1.0 force-response-1.0
  # MSIE 7 and newer should be able to use keepalive
  BrowserMatch "MSIE [17-9]" ssl-unclean-shutdown

How To Report A Bug

From Hacker News to the Greatest Bug I Never Fixed to a wonderful comment in the Perl doc forums:

I submitted a proposal to OSCON called “How To Report A Bug” about the social issues involved in reporting and accepting bug reports. Its still pending, but its caused me to do a little writing for it. I came up with this introduction which I feel sums up the problem well. I’m also tickled that one measures bug report frustration in bags of shit.

Developers often treat bug reports like someone dumping a bag of shit on your doorstep, ringing the bell and telling you to clean it up. That’s not what they are. A bug report is someone pointing out that there’s some shit on your doorstep, they stepped in it, and maybe it should be cleaned up.

Either way, nobody likes stepping in shit. And nobody likes cleaning up shit. So the whole interaction starts off on the wrong foot, perhaps the one covered in shit. Your job, as developer or as reporter, is to deliberately steer it back to being a positive one where the developer wants to fix shit and the reporter wants to continue to report shit.

How To Report A Bug

Installing Tortoise Git for Windows


I’ve used Tortoise SVN for years and it makes things really easy for getting started with Subversion and integrating smoothly with Windows. However Git is a more confusing world. There’s two installations and neither one clearly refers to the other.

However it boils down to the following (you can accept all the defaults in the installation):

  1. Install Git for Windows (
  2. Install Tortoise Git (

ntwdblib download


For years I have had problems running the mssql driver. Its getting phased out – i.e. it doesn’t work with PHP 5.3 but if you have to support older applications then you need to use the mssql driver. The problem is, is that the default installation of PHP 5.2 (currently PHP 5.2.17) which you can download from just doesn’t work with the mssql driver.

The problem is the ntwdblib.dll. The version that has always worked for me is 2000.80.194.0 – all others fail. The version that comes with the PHP msi installer (I use the 64 bit installer) is version 2000.80.2039, which should in theory be newer and work better. So each time I install PHP I then have to go in and overwrite the dll.

The next problem you have is finding a reliable dll. The proper way to get it is from the SQL Server 2000 SP4 installation (yes, the file is that old). If you google for the file there’s no pages that I find that seem a trust worthy resource for this file.

So I’ve uploaded the file to my site n.b. its a different site from this WordPress blog as I doubt will allow me to upload dlls.