lilypond.sty

\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{lilypond}

\RequirePackage{xkeyval}
\RequirePackage{graphicx}

\newlength{\lilypond@staffsize}
\newlength{\lilypond@betweensystemspace}
  \setlength{\lilypond@betweensystemspace}{20mm}
\DeclareOptionX{staffsize}[0]{\setlength{\lilypond@staffsize}{#1pt}}
\DeclareOptionX{between-system-space}[20]{%
  \setlength{\lilypond@betweensystemspace}{#1mm}}
\ProcessOptionsX

\newcommand{\lilypondfile}[1]{%
  \newwrite\conffile
  \immediate\openout\conffile\jobname.lil
  \immediate\write\conffile{[General]}
  \immediate\write\conffile{filename: #1.ly}
  \immediate\write\conffile{columnwidth: \the\columnwidth}
  \immediate\write\conffile{}
  \immediate\write\conffile{[Options]}
  \immediate\write\conffile{staffsize: \the\lilypond@staffsize}
  \immediate\write%
    \conffile{between-system-space: \the\lilypond@betweensystemspace}
  \immediate\closeout\conffile
  \par
  \IfFileExists{#1.eps}{\noindent\includegraphics{#1}}{}
  \par
}