\par
\section{Data Structure}
\label{section:Lock:dataStructure}
\par
The {\tt Lock} structure has three fields.
\begin{itemize}
\item {\tt int nlocks} : number of locks made.
\item {\tt int nunlocks} : number of unlocks made.
\item the mutual exclusion lock
\par
For Solaris threads we have {\tt mutex\_t *mutex}.
\par
For POSIX threads we have {\tt pthread\_mutex\_t *mutex}.
\par
For no threads we have {\tt void *mutex}.
\end{itemize}

