33 lines
1.9 KiB
HTML
33 lines
1.9 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>6.2.5 Notes on half-duplex pipes:</TITLE>
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<A NAME="tex2html499" HREF="node15.html"><IMG WIDTH=37 HEIGHT=24 ALIGN=BOTTOM ALT="next" SRC="next_motif.gif"></A> <A NAME="tex2html497" HREF="node9.html"><IMG WIDTH=26 HEIGHT=24 ALIGN=BOTTOM ALT="up" SRC="up_motif.gif"></A> <A NAME="tex2html493" HREF="node13.html"><IMG WIDTH=63 HEIGHT=24 ALIGN=BOTTOM ALT="previous" SRC="previous_motif.gif"></A> <A NAME="tex2html501" 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="tex2html500" HREF="node15.html">6.3 Named Pipes (FIFOs </A>
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<B>Up:</B> <A NAME="tex2html498" HREF="node9.html">6.2 Half-duplex UNIX Pipes</A>
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<B> Previous:</B> <A NAME="tex2html494" HREF="node13.html">6.2.4 Atomic Operations with </A>
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<BR> <P>
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<H2><A NAME="SECTION00725000000000000000">6.2.5 Notes on half-duplex pipes:</A></H2>
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<P>
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<UL><LI> Two way pipes can be created by opening up two pipes, and properly
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reassigning the file descriptors in the child process.<LI> The pipe() call must be made BEFORE a call to fork(), or the descriptors
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will not be inherited by the child! (same for popen()).<LI> With half-duplex pipes, any connected processes must share a related
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ancestry. Since the pipe resides within the confines of the kernel, any
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process that is not in the ancestry for the creator of the pipe has no
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way of addressing it. This is not the case with named pipes (FIFOS).
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</UL><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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