Special Considerations for Running with Shared Memory
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When using the ch_shmem or ch_lfshmem devices with System V
shared memory, processes that exit abnormally (e.g., with a segmentation
violation) may leave System V semaphores or shared memory segments
allocatedSurprisingly, the System V IPC (interprocess communication)
mechanisms do not have a ``delete on unreferenced'' attribute.
Since there is usually a limited number of these objects, it is important to
recover them. The Unix command ipcs can be used to list the allocated
semaphores and shared memory segments, and ipcrm can be used to delete
them. The script bin/cleanipcs can be used to identify and delete
all System V IPCs owned by the calling user; the use is simply
bin/cleanipcs
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