- Added code to read SANS TOF frames from a) files and b) from HM

- Fixed an bug causing core dumps on bad Tcl scripts
- Started on a syntax checker for SICS

utils/check/sicssyntax.tex

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+\documentclass[12pt,a4paper]{article}
+%%\usepackage[dvips]{graphics}
+%%\usepackage{epsf}
+\setlength{\textheight}{24cm}
+\setlength{\textwidth}{16cm}
+\setlength{\headheight}{0cm}
+\setlength{\headsep}{0cm}
+\setlength{\topmargin}{0cm}
+\setlength{\oddsidemargin}{0cm}
+\setlength{\evensidemargin}{0cm}
+\setlength{\hoffset}{0cm}
+\setlength{\marginparwidth}{0cm}
+
+\begin{document}
+\begin{center}
+\begin{Large}
+SICS Syntax Checker\\
+Implementation Notes\\
+\end{Large}
+Mark K\"onnecke\\
+Mark.Koennecke@psi.ch\\
+March/April 2003\\
+Laboratory for Neutron Scattering\\
+Paul Scherrer Institute\\
+CH--5232 Villigen--PSI
+Switzerland
+\end{center}
+
+Users wish to check their batch files for syntax errors before
+submitting them to SICS for the weekend or the night. Unfortunately
+checking SICS syntax is not so easy as it consists of Tcl syntax plus
+SICS commands. In order to implement a syntax checker various
+possibilities exist:\begin{itemize}
+\item Implement the syntax checker as a calculation mode within
+SICS. This has the disadvantage that the syntax check can only be run
+by one person and only when the SICS server is not performing an
+experiment. This is due to the fact, that SICS has only one set of
+variables which may be changed dureing the syntax check. In order to
+prevent corruption the security measures stated above are necessary.
+\item Use a SICServer with simulated hardware. This would
+work. Problems are that this is very time consuming to set up and the
+synchronisation of parameter values with the main SICServer. This has
+been solved through the sync command and thus this option is available
+for complex scripts. 
+\item Use a Tcl interpreter with dummy SICS commands as a syntax
+checker. In many cases batch files are fairly simple and a complete
+simulation is not needed. The such a option would be sufficient.   
+\end{itemize}
+\end{document}
+
+\section{The Tcl Syntax Checker}
+This section describes the syntax checker built from a Tcl interpreter
+with dummy routines testing SICS syntax. The dummy procedures only
+have to test the syntax and else do nothing. Not many such proecdures
+have to be implemented but a means is needed for mapping names, for
+instance motor names, to a suitable procedure for checking the syntax.
+
+This syntax checker can be used in a variety of situations:
+\begin{itemize}
+\item Standalone: the preferred mode of operation
+\item Within SICS: SICS would need to have a second Tcl interpreter
+for this purpose in order to prevent corruption of the main
+interpreter. Even then a rogue script could go into an endless loop
+and thus hang the SICS server. Thus this second interpreter would have
+to run as a separate process or thread. 
+\item This syntax checker could also help debugging SICS scripts.
+\end{itemize}
+
+For each instrument two files are needed for this syntax checker.  The
+first is a common library file which implements the syntax checking
+procedures and the sics_alias procedure which maps names to
+procedures. The second is a mapping file which defines the instrument
+and enables those names the instrument provides. This is much like the
+instrument initialization file for the main SICS program.
+
+In order to help in script debugging, a global array with parameter
+values defined through the user script will be maintained. 
+
+In a latter stage a connection to the main SICS could be added to the
+system. Through this  connection the actual configuration of the
+instrument could be queried. Also parameter values can be updated in
+order to help in debugging sophisticated scripts.  Moreover this
+connection could be used to check limit violations. 
+
+
+