--- vladimir@worklogic.com: this below isn't implemented yet! ---
--- Talk to me if you're interested in it and want to help ---
                           Latex/Psfrag Attributes+
Only work in -Tps and if latex2e and psfrag.sty ver.3 are installed.
  The resulting ps file will print latex commands unless you include it in a
tex file that does \usepackage[scanall]{psfrag}, or run it through the
supplied script "psfrag" (which wraps it in such a tex file).

psfrag: string [GNE]. This text is passed through latex. 
  Example: node: a1 [psfrag="$\alpha_1$"]
           edge: x->y [label="x -> y" psfrag="$x \rightarrow y$"] 
  The name/label is used only as a guide for positioning, but you better
  specify them. E.g. if the edge had no label attribute, dot would have to
  assume that the label is 17 characters wide.
    The line breaks \l,\n,\r are *not* processed in the psfrag attribute.
  If you want line breaks, arrange it with latex commands, and *also* specify
  a label that emulates the breaks.
tailpsfrag/headpsfrag: string [E]. Same for tail/head of the edge.
fontname: [GNE] Use any of the commands described in latex2e's fntguide.
  If the command sequence contains %s, the text is inserted there. Else the
  text is preceded by the command, all surrounded by braces. For example, if
  the text is "..." then \texttt{%s} becomes \texttt{...}, and \ttfamily
  becomes {\ttfamily ...}. 
    If fontname matches "tt" then dot will use fixed font width for its
  positioning (is 0.65 right??). If fontname matches "bf" then dot will
  multiply the width for positioning purposes by ?? (for all families??).
    You cannot change the font by simply giving a different font name.
  E.g. to switch to Courier, you either have to use \texttt{%s} with a style
  that uses Postscript fonts, or else use \fontfamily{pcr}\selectfont ("pcr"
  stands for postscript courier). As a precaution, dot won't output a fontname
  that does not contain \.
    Often used commands are \rmfamily (roman), \sffamily (sans serif),
  \ttfamily (typewriter), \mdseries (medium, i.e. normal), \bfseries (bold),
  \upshape (upright, i.e. normal), \itshape (italic), \slshape (slanted),
  \scshape (small caps); or their equivalents \textrm{%s}, ...; \boldmath;
  \mathcal{%s}.
fontsize: "n\cmd". [GNE] Dot assumes for positioning purposes that the font is
  n points high, and emits the font changing command \cmd to latex. Both n and
  \cmd are optional.
    If \cmd is missing then you are informing dot that the latex fontsize is n.
  *Please* do this at the top level. The default 14 is probably wrong for you.
  The correct setting for a 10pt article style is "digraph G {fontsize=10 ...}"
    If you use "n!", dot will force this size to latex by emitting commands
  \fontsize\selectfont. This is not smart unless you use scalable fonts, eg
  postscript fonts. 
    If n is missing and \cmd is one of the standard commands \tiny,
  \scriptsize, \footnotesize, \normalsize, \large, \Large, \LARGE, \huge or
  \HUGE, dot will compute the new size automatically. Otherwise you have to
  specify both.
    If the command contains %s, the text will be inserted there, else the
  text is preceded by the command, all surrounded by braces.