=================================================================== RCS file: /home/cvs/OpenXM/doc/issac2000/openxm-stackmachines.tex,v retrieving revision 1.9 retrieving revision 1.14 diff -u -p -r1.9 -r1.14 --- OpenXM/doc/issac2000/openxm-stackmachines.tex 2000/01/15 12:18:42 1.9 +++ OpenXM/doc/issac2000/openxm-stackmachines.tex 2000/01/17 08:50:56 1.14 @@ -1,4 +1,4 @@ -% $OpenXM: OpenXM/doc/issac2000/openxm-stackmachines.tex,v 1.8 2000/01/15 03:46:27 noro Exp $ +% $OpenXM: OpenXM/doc/issac2000/openxm-stackmachines.tex,v 1.13 2000/01/17 08:06:15 noro Exp $ \section{OpenXM Stack machines}\label{sec:ox-stackmachines} @@ -7,13 +7,27 @@ In OpenXM specification, all servers are stack machine When a server ox\_xyz gets an OX data message, it translates the data into a local object of ox\_xyz and pushes the object onto the stack. -According to the OpenMath specification, -the translation scheme together with definitions of mathematical operations -of the system ox\_xyz is called the {\it PhraseBook} of ox\_xyz. +The translation scheme +%% together with definitions of mathematical operations +%% of the system ox\_xyz +is called the {\it PhraseBook} of ox\_xyz (cf. OpenMath \cite{OpenMath}). +For example, the Asir command {\tt ox\_push\_cmo(P,1)} +(push integer $1$ onto the server $P$) +sends an OX data message +{\tt (OX\_DATA,(CMO\_ZZ,1))} to the server $P$. +Here, +{\tt OX\_DATA} stands for {\tt OX\_DATA} header and +{\tt (CMO\_ZZ,1)} is a body standing for $1$ expressed +by the CMO. +The server translates {\tt (CMO\_ZZ, 1)} to its internal object of +the integer $1$ +and pushes the object onto the stack. +If the server gets an {\it OX command} message, then the server +executes the command. Any OX command message starts with the int32 tag OX\_COMMAND. -The body is an OpenXM stack machine operation code expressed by int32. -The codes are listed below. +The body is a stack machine operation code expressed by int32. +The codes are listed below \cite{noro-takayama}. \begin{verbatim} #define SM_popSerializedLocalObject 258 #define SM_popCMO 262 @@ -45,7 +59,7 @@ First, arguments for a mathematical operation and the number of the arguments are pushed. Second, the mathematical operator name, -such as {\tt fctr} (asir factorization command), +such as {\tt fctr} (the factorization command of Asir), is pushed as a string. Finally, the stack machine command {\tt SM\_executeFunction} (269) evaluates the operator and @@ -53,31 +67,34 @@ pushes the result onto the stack after poping the operator name, the number of arguments and arguments. For example, the following code factorizes $x^{100}-1$ by calling -{\tt ox\_asir} from asir. +{\tt ox\_asir} from Asir. \begin{verbatim} P = ox_launch(); ox_push_cmo(P,x^100-1); ox_push_cmo(P,ntoint32(1)); -ox_push_cmd(P,269); +ox_push_cmo(P,"fctr"); ox_push_cmd(P,269); Ans = ox_pop_cmo(P); \end{verbatim} When an error has occurred on an OpenXM server, -an error object is pushed to the stack instead of a result of the computation. +an error object is pushed onto the stack +instead of a result of the computation. The error object consists of the serial number of the OX message which caused the error, and an error message. \begin{verbatim} -[341] ox_rpc(0,"fctr",1.2*x)$ -[342] ox_pop_cmo(0); +[340] P = ox_launch()$ +[341] ox_rpc(P,"fctr",1.2*x)$ +[342] ox_pop_cmo(P); error([8,fctr : invalid argument]) \end{verbatim} OpenXM server won't send error messages to the client except when it receives a {\tt SM\_pop*} command. -OX stackmachines work in the asynchronous mode which is similar +OX stack machines work in the asynchronous mode which is similar to X servers. -For servers for graphic and sound applications, it is an advantageous feature. -It is also easy to emulate RPC and a web server for MCP \cite{iamc} -on our asynchronous OX stackmachines. +For servers of graphic and sound applications, +it may be an advantageous feature. +It is also possible to emulate RPC and a web server for MCP \cite{iamc} +on our asynchronous OX stack machines.