59 lines
2.3 KiB
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59 lines
2.3 KiB
HTML
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<!--Converted with LaTeX2HTML 96.1-c (Feb 29, 1996) by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds -->
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<TITLE>Kernel msg structure</TITLE>
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<A NAME="tex2html771" HREF="node32.html"><IMG WIDTH=37 HEIGHT=24 ALIGN=BOTTOM ALT="next" SRC="next_motif.gif"></A> <A NAME="tex2html769" HREF="node29.html"><IMG WIDTH=26 HEIGHT=24 ALIGN=BOTTOM ALT="up" SRC="up_motif.gif"></A> <A NAME="tex2html763" HREF="node30.html"><IMG WIDTH=63 HEIGHT=24 ALIGN=BOTTOM ALT="previous" SRC="previous_motif.gif"></A> <A NAME="tex2html773" HREF="node1.html"><IMG WIDTH=65 HEIGHT=24 ALIGN=BOTTOM ALT="contents" SRC="contents_motif.gif"></A> <BR>
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<B> Next:</B> <A NAME="tex2html772" HREF="node32.html">Kernel msqid_ds structure</A>
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<B>Up:</B> <A NAME="tex2html770" HREF="node29.html">Internal and User Data </A>
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<B> Previous:</B> <A NAME="tex2html764" HREF="node30.html">Message buffer</A>
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<BR> <P>
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<H4><A NAME="SECTION00742220000000000000">Kernel <TT>msg</TT> structure</A></H4>
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<P>
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The kernel stores each message in the queue within the framework of the <TT>msg</TT> structure.
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It is defined for us in <TT>linux/msg.h</TT> as follows:
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<P>
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<P>
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<HR><PRE>/* one msg structure for each message */
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struct msg {
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struct msg *msg_next; /* next message on queue */
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long msg_type;
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char *msg_spot; /* message text address */
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short msg_ts; /* message text size */
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};</PRE>
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<HR><DL ><DT><STRONG><TT>msg_next</TT></STRONG>
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<DD>
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<P>
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This is a pointer to the next message in the queue. They are stored as a
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singly linked list within kernel addressing space.
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<P>
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<DT><STRONG><TT>msg_type</TT></STRONG>
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<DD>
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<P>
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This is the message type, as assigned in the user structure <TT>msgbuf</TT>.
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<P>
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<DT><STRONG><TT>msg_spot</TT></STRONG>
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<DD>
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<P>
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A pointer to the beginning of the message body.
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<P>
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<DT><STRONG><TT>msg_ts</TT></STRONG>
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<DD>
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<P>
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The length of the message text, or body.
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<P>
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</DL><BR> <HR>
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<P><ADDRESS>
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<I>Converted on: <BR>
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Fri Mar 29 14:43:04 EST 1996</I>
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