40 lines
2.1 KiB
HTML
40 lines
2.1 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>IPC Identifiers</TITLE>
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<A NAME="tex2html663" HREF="node24.html"><IMG WIDTH=37 HEIGHT=24 ALIGN=BOTTOM ALT="next" SRC="next_motif.gif"></A> <A NAME="tex2html661" HREF="node22.html"><IMG WIDTH=26 HEIGHT=24 ALIGN=BOTTOM ALT="up" SRC="up_motif.gif"></A> <A NAME="tex2html655" HREF="node22.html"><IMG WIDTH=63 HEIGHT=24 ALIGN=BOTTOM ALT="previous" SRC="previous_motif.gif"></A> <A NAME="tex2html665" 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="tex2html664" HREF="node24.html">IPC Keys</A>
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<B>Up:</B> <A NAME="tex2html662" HREF="node22.html">6.4.1 Fundamental Concepts</A>
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<B> Previous:</B> <A NAME="tex2html656" HREF="node22.html">6.4.1 Fundamental Concepts</A>
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<BR> <P>
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<H3><A NAME="SECTION00741100000000000000">IPC Identifiers</A></H3>
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<P>
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Each IPC <EM>object</EM> has a unique IPC identifier associated with it. When
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we say ``IPC object'', we are speaking of a single message queue, semaphore set,
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or shared memory segment.
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This identifier is used within the kernel to uniquely identify an IPC object.
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For example, to access a particular shared memory segment, the only item you
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need is the unique ID value which has been assigned to that segment.
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<P>
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The uniqueness of an identifier is relevant to the <EM>type</EM> of object
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in question. To illustrate this, assume a numeric identifier of ``12345''.
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While there can never be two message queues with this same identifier, there
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exists the distinct possibility of a message queue and, say, a shared memory
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segment, which have the same numeric identifier.
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<P>
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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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