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Top Forums Programming IPC - pipes between parent and child process Post 302473584 by DGPickett on Sunday 21st of November 2010 02:01:25 PM
Old 11-21-2010
Well, it sounds like you need a protocol, or operate your pipes full duplex with at state machine at each end to take care of activities on that overlaid protocol. Decoding & analyzing professors is much more complex than decoding & analyzing an API. Smilie

If you find pipes, sockets, shmem, semaphores, queues and all that a bit restrictive, you can mmap() a file in both processes, creating an area of shared memory, not to be confused with the silly UNIX ipc shared memory that needs root setup and such dusty old stuff, and the nice thing is that you can peek at the mmap90'd file during or after for you edification about what is going on. It is really fast, RAM write snoop invalidating cache fast. You can even have a file for each writer, so there is no ambiguity about who put the file in that state.
 

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shmem(5)							File Formats Manual							  shmem(5)

NAME
shmem - enable or disable System V shared memory DESCRIPTION
The tunable is obsolete. The System V IPC shared memory subsystem is always enabled. Shared memory is an efficient InterProcess Communications (IPC) mechanism. One process creates a shared memory segment and attaches it to its address space. Any processes looking to communicate with this process through the shared memory segment, then attach the shared memory segment to their corresponding address spaces as well. Once attached, a process can read from or write to the segment depending on the permissions specified while attaching it. WARNINGS
Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parameter values. After installation, some tunable parameters may no longer be at the default or recommended values. For information about the effects of installation on tun- able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was factory installed on your system, see at AUTHOR
was developed by HP. SEE ALSO
shmmax(5), shmmni(5), shmseg(5). Tunable Kernel Parameters shmem(5)
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