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Full Discussion: Shared Memory (Posix)
Top Forums UNIX for Advanced & Expert Users Shared Memory (Posix) Post 302194255 by jim mcnamara on Monday 12th of May 2008 02:28:18 PM
Old 05-12-2008
This sounds like school assignment. The differences are not that great. We do not support school work here.

This page has examples of both. N ote the "POSIX" section is not all that big:
IPC:Shared Memory
Read the one paragraph on POSIX. Use all of the rest of the examples, change open() calls to shm_open() and close() to shm_unlink(). And there you are.
system V -> POSIX.
 

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LEARN ABOUT HPUX

shmem

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       The tunable is obsolete.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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