48 lines
1.5 KiB
Text
48 lines
1.5 KiB
Text
From: Nico Schottelius
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Subject: Unix IPC, socket/AF_UNIX; bind on r/o devices?
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Date: 09 May 2005 09:51:27 GMT
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To: comp.unix.programmer
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Hello!
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Situation:
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- everything mounted readonly (as when starting the system)
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- one process with n children, which may have n children (recursive)
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- all the children and children of children should be able to talk to the
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first parent
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Problem:
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- Using bind() will fail, because
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a) socket cannot created
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b) the existing socket cannot be reused
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Other possibilities not working:
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- shared memory is not an option, as one need
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-lrt, which needs -lpthread, which is problematic to link statically
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- pipes: handling the pipes from parent to child of child of child
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would be hard to program
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- socketpair: should be the same problematic as it's with pipes
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- fifos: one would have to create the fifos before and two fifos
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for each child; possible, but very unelegant; and one would have
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to memorize, which child is connected to which fifo; again possible,
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but somehow unelegant
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- signaling: one could implement communication with some kind of
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morse code with signals, but that won't be a good solution
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Questions:
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- Is there any way, case b) (socket already existing) can be solved in
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a way that I tell bind() to use an existing socket?
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- What would be the best solution to talk bidirectional to clients
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in this scenario?
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I appreciate any hint, as I really like the socket mechanism and would
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like to keep it.
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Thanks in advance,
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Nico
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