Ah, thanks! So it was configuration then...

I initially figured it was language-dependant, which was why I tried it in
Ruby, since "$" is a valid character in that language... What I didn't
anticipate was that the boxes came from intelligent-syntax checking--I
figured that it was just some sort of fancy character I was unfamiliar with
that needed to be escaped.

So, the way I fixed the issue in my Org file was to add the following to
override the syntax error checking:

    #+LATEX_HEADER: \expandafter\def\csname PY@tok@err\endcsname{}

It was recommended on that Stack Exchange answer not to do this, but we
aren't writing code directly in LaTeX, we're using Org mode..! That means
we don't really need error highlighting in our exporting, since that sort
of thing is already covered by existing language support.

On Fri, Sep 4, 2015 at 5:57 AM, Alan Schmitt <alan.schmitt@polytechnique.org
> wrote:

> (Still catching up on orgmode mail … sorry if you already found a way to
> address the issue)
>
> On 2015-08-18 18:13, Matthew MacLean <archenoth@gmail.com> writes:
>
> > When working with Org Babel source code blocks, if I have a dollar sign
> in my
> > code and export it to PDF using LaTeX, it appears to parse as an internal
> > link. (Maybe?)
> >
> > This is what it looks like:
> > Inline image 1
> > That comes from the following source code block:
> >
> > #+BEGIN_SRC sql :eval no :var id=1
> > SELECT * FROM blah
> > WHERE id=$id
> > #+END_SRC
> >
> > The resulting LaTeX from the source code block is:
> >
> > \begin{minted}[]{sql}
> > SELECT * FROM blah
> > WHERE id=$id
> > \end{minted}
> >
> > I have verified that SQL is not the only block type to do this by having
> a
> > Ruby block with nothing except a "$" in it, and got the same result.
>
> These red boxes often come from signaling a syntax error from pygments,
> which I confirmed by putting the code in a test.sql file and running:
>
> % pygmentize -f latex test.sql
> \begin{Verbatim}[commandchars=\\\{\}]
> \PY{k}{SELECT} \PY{o}{*} \PY{k}{FROM} \PY{n}{blah}
> \PY{k}{WHERE} \PY{n}{id}\PY{o}{=}\PY{err}{\PYZdl{}}\PY{n}{id}
> \end{Verbatim}
>
> You can see the “\PY{err}” that signals a parser error around the dollar
> sign.
>
> There are some solutions to hide these boxes here:
>
> http://tex.stackexchange.com/questions/14166/red-box-drawn-around-question-mark-operator-in-minted-erlang-code
>
> Best,
>
> Alan
>
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