PSI sics-cvs-psi_pre-ansto

doc/programmer/alias.tex

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+\subsection{The Alias Facility}
+Aliases make commands available under a different name. SICS currently supports two types of aliases:
+\begin{itemize}
+\item Object aliases. This is a facility for renaming first class SICS
+objects such as commands and hardware objects. This is installed into
+SICS by creating a new name in the interpreter but with the data
+structures of the original object. Thus all interface operations such
+as driving etc will work. Object aliases are installed from the
+initialization script through the SicsAlias command.  
+\item Command aliases. This is just plain text replacement. For
+instance one may define ``sttll'' instead of ``a4 softlowerlim''. Such
+an alias can be installed with the ``alias'' command at any
+time. However, renaming a motor with this scheme will not work
+properly as this alias facility has no way to forward interfaces
+properly.        
+\end{itemize}
+There is no
+data structure associated with object aliases. The trick is done by
+just  putting in
+the same command as a new name into the interpreter.
+ 
+ Corrspondingly there is only one function to it:
+\begin{verbatim}
+  int SicsAlias(SConnection *pCon, SicsInterp *pSics, void *pData,
+                int argc, char *argv[]);
+\end{verbatim}
+SicsAlias is the object wrapper function which implements the alias command.
+                  				
+
+Command aliases are implemented through:
+\begin{verbatim}
+  int MakeAlias(SConnection *pCon, SicsInterp *pSics, void *pData,
+                int argc, char *argv[]);
+\end{verbatim}
+There is a little trivial data structure associated with command
+aliases which is defined in alias.c.
+