diff options
| -rw-r--r-- | doc/info/mds.texinfo | 44 |
1 files changed, 41 insertions, 3 deletions
diff --git a/doc/info/mds.texinfo b/doc/info/mds.texinfo index 2c89cd2..6da25d8 100644 --- a/doc/info/mds.texinfo +++ b/doc/info/mds.texinfo @@ -342,7 +342,10 @@ of crashing. @cpindex Layers, architecture @cpindex Architectural layers @cpindex Kernel +@cpindex Display server kernel +@pgindex @command{mds} @cpindex Master server +@pgindex @command{mds-server} The @command{mds} display server in architectured in three layers. The first layer is called the kernel. The kernel is responsible for acquiring a display @@ -363,6 +366,7 @@ mission falls to the master server. @cpindex Message passing, coordination @cpindex Communication, coordination @cpindex Interprocess communication, coordination +@pgindex @command{mds-server} The second layer is the master server. The master server has two responsibilities: coordinating message passing between other servers and clients @@ -399,6 +403,7 @@ of the display server. @cpindex Communication, mechanism @cpindex Interprocess communication, mechanism @cpindex Master server +@pgindex @command{mds-server} Intrinsic to @command{mds} is a powerful interprocess communication mechanism. Servers and clients connect to the display server by @@ -424,6 +429,7 @@ Join or leave a multicast group. @cpindex Assignment of ID @cpindex Disconnection @cpindex Master server +@pgindex @command{mds-server} Upon assignment of an ID the master server will automatically place the client in a multicast group for that specific client. @@ -439,6 +445,7 @@ the client, refered to by it's ID, have closed. @cpindex Interprocess communication, message structure @cpindex Message structure, message passing @cpindex Master server +@pgindex @command{mds-server} A message in the @command{mds} protocol is comprised of two parts: headers and a payload. When a client joins a multicast group it is @@ -456,6 +463,7 @@ multicasted to groups indicated by its headers. @cpindex Interprocess communication, message modification @cpindex Message modification, message passing @cpindex Master server +@pgindex @command{mds-server} @cpindex Multicast groups The multicast groups and receiving of message is called interceptions. The interesting @@ -700,6 +708,8 @@ unavailable when running under @command{valgrind}. @cpindex Interprocess communication, filesystem @cpindex Filesystem @cpindex Kernel +@cpindex Display server kernel +@pgindex @command{mds} The @command{mds} kernel creates two directories for the @command{mds} servers to use: one for runtime data and one for temporary data. @@ -756,6 +766,12 @@ its servers and clients. @node Message Passing @section Message Passing +@cpindex Message passing, display +@cpindex Communication, display +@cpindex Interprocess communication, display +@cpindex Kernel +@cpindex Display server kernel +@pgindex @command{mds} Message passing over domain sockets is the underlaying technique for communicating with the display server. To communicate with the @@ -764,6 +780,10 @@ must connect to the domain socket created by the display server kernel as named in @ref{Filesystem}. +@cpindex Connecting to the display +@cpindex Client ID assignment +@cpindex ID assignment +@cpindex Assignment of ID Clients should request a unique ID when it connects to the display server.@footnote{There is seldom a reason for servers to do this.} @@ -777,6 +797,9 @@ Message ID: 0\n @end group @end example +@cpindex Message ID +@cpindex Message corruption +@cpindex Corrupt messages where @code{\n} is an LF-line break. The value on the @code{Message ID} line does not need to be 0, but servers and @@ -787,13 +810,17 @@ must contain this @code{Message ID} header, otherwise the message is considered corrupt and is ignored. +@cpindex Message structure +@cpindex Message passing, message structure +@cpindex Communication, message structure +@cpindex Interprocess communication, message structure The empty line signifies the end of the header list, and in this case the end of the message. But a message may contain payload beneath this empty line. To include a payload, add the header @code{Length} that says how many bytes -the payload is comprised of. +the payload is comprised. A header must contain a header name and header value without any trailing or @@ -801,6 +828,11 @@ leading spaces, and `: ' (colon, one regular blank space) exactly delimits the name and the value. +@cpindex Master server +@pgindex @command{mds-server} +@cpindex Client ID assignment +@cpindex ID assignment +@cpindex Assignment of ID When the master server receives this @code{Command: assign-id} message it will assign the client a unique ID @@ -827,6 +859,7 @@ In response to: 0\n @end group @end example +@cpindex Message ID Notice that the master server never includes @code{Message ID} in message originating from it. @@ -837,12 +870,13 @@ a colon (`:'). Both of these integers are unsigned 32-bit integers. This is done this way because unsigned 64-bit integers are forbidden because it is -not supportable natively be some +not supported natively be some programming languages. Before a client has gotten a unique client ID assigned to it, it will be `0:0'. +@cpindex Disconnection If a client gets disconnected from the master server, the master server will sends out a signal header message. @@ -868,6 +902,10 @@ Client closed: 0:0\n @end group @end example +@cpindex Addressing message +@cpindex Message passing, addressing +@cpindex Communication, addressing +@cpindex Interprocess communication, addressing Once a client has an unique client ID assigned to it, it should always include the header @code{Client ID} in its @@ -1688,6 +1726,7 @@ to starta process in a new process group. @pgindex @command{mds} @pgindex @command{mds-server} @cpindex Kernel +@cpindex Display server kernel @cpindex Master server An @command{mds} display server instance is comprised of multiple small servers that each implements a small part @@ -11501,7 +11540,6 @@ TODO application menu features: TODO In `Rat Cursors` use anchors and references to hyperlink names. TODO Indices: - Protocol → Message Passing Protocol → Interception Protocols Default Keyboard Layouts |