oracular ramblings

Hopefully this will help somebody else avoid the ‘fun’ of trying to track down why, exactly, LaTeX has suddenly gotten cranky, and (under OSX) the TeXShop ‘typeset’ command suddenly started dying miserably with:

pathsea: Running mktexmf ptmr7t
! I can't find file `ptmr7t'.
<*> ...:=ljfour; mag:=1; nonstopmode; input ptmr7t

Please type another input file name
! Emergency stop.
<*> ...:=ljfour; mag:=1; nonstopmode; input ptmr7t

A few quick basics — I’m running TeXShop as my front end, with the handy BasicTeX package (discussed halfway down the page) for a lightweight TeX backend on OS X 10.4.11.

It’s a bit embarrassing to admit that I hadn’t noticed that there was an issue with generating pdfs from TeXShop until some well intentioned directory cleanup. It appears that TeXShop will cheerfully show you an existing pdf by the appropriate name if one exists, and it can’t actually typeset the new version… sans error!

Once I’d discovered that there was a problem, the yak shaving began. Skipping over the chasing faint hints and vague suggestions, I found the following:

• IEEEtran clearly included something problematic
• This debian bug report which pointed out that the ‘ptmr7t’ font wasn’t included in the base TeX Live install.
• An exceedingly simple document resulted in the failure:

      \documentclass{article}
        \usepackage{times}
        \title{Brief Article}
        \author{The Author}
        \begin{document}
        \maketitle
        This is a test!
      \end{document} 

• It’s bloody hard to find what’s actually missing.

As it turns out, the problem seems to be that the PSNFSS macros only included the font description (.fd) and style (.sty) files … which wouldn’t matter if the psnfss definitions weren’t used for a number of basic things, including various math functions.

You can download the whole PSNFSS package — but the missing fonts for ptmr7t et al were in lw35nfss.zip.

From there, I extracted the fonts, and:

• Copied the extracted fonts from ./psnfss/fonts/[vf|tfm] over to $texlive/…/texmf-dist/fonts/[vf|tfm]
• Ran ‘texhash’ and ‘mktexlsr’ (it’s possible that I only needed one or the other, but I wasn’t about to try and break things again, just to see)

Hope that helps… or at least reduces your yak shaving!

After I found out that my LISA ‘07 talk about The Security Butterfly Effect had been scheduled for 2pm on Friday – the last day of the conference, and just before closing ceremonies – I decided my job was edutainment, more than education.

I’m prone to involving my audience in the talk at the best of times – and this was no exception. Heckling was welcome and encouraged, and audience participation was as mandatory as possible with your average herd of sysadmins.

That aside, the general gist of the talk is this:

“Small variations in the initial condition of a system may produce large variations in the long term behaviour of the system”

Most of us don’t actually know what the initial condition of our system (environment, if you prefer) is. As such, we make countless assumptions every day about the initial state of our system. With the increase in automation and automated processing of information, the assumptions that we’re functioning under are often neither ours, nor visible to us. The rise of the machines and vast increases in complexity make it easy to miss that first small misstep that leads to later, catastrophic events.

A much more interesting topic that I didn’t really explore is the interaction of complex systems, where singly innocuous changes become serious vulnerabilities in combination.

I always have a dreadful time setting out to write, whether it’s writing a blog post (as you can see!), writing a paper, or writing an article. The only thing that seems to flow freely is pithy responses to mailing lists.

Given that, I was happy to find the following set of links, starting at the excellent Light Blue Touchpaper with How (not) to write an abstract, following a comment link to Microsoft’s Simon Peyton Jones delightfully pithy presentation about writing a paper, and finally ending up at a lovely collection of links put together by Mark Leone, and referred to at the end of spj’s presentation.