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sc::ShmMemoryGrp Class Reference The ShmMemoryGrp concrete class provides an implementation of MsgMemoryGrp. More... #include <memshm.h> Inheritance diagram for sc::ShmMemoryGrp: [legend]Collaboration diagram for sc::ShmMemoryGrp: [legend]List of all members. Public Methods   ShmMemoryGrp (const Ref< MessageGrp > &msg)   ShmMemoryGrp (const Ref< KeyVal > &)   ~ShmMemoryGrp () void  set_localsize (size_t)   Set the size of locally held memory. More... void *  localdata ()   Returns a pointer to the local data. void *  obtain_readwrite (distsize_t offset, int size)   Only one thread can have an unreleased obtain_readwrite at a time. More... void *  obtain_readonly (distsize_t offset, int size)   This gives read access to the memory location. No locking is done. void *  obtain_writeonly (distsize_t offset, int size)   This gives write access to the memory location. No locking is done. void  release_readonly (void *data, distsize_t offset, int size)   This is called when read access is no longer needed. void  release_writeonly (void *data, distsize_t offset, int size)   This is called when write access is no longer needed. void  release_readwrite (void *data, distsize_t offset, int size)   This is called when read/write access is no longer needed. More... void  print (std::ostream &o=ExEnv::out0()) const   Prints out information about the object. Detailed Description The ShmMemoryGrp concrete class provides an implementation of MsgMemoryGrp. It uses SYSV IPC to provided shared memory in a system that provide shared memory in hardware. It is very fast and reliable. Member Function Documentation void* sc::ShmMemoryGrp::obtain_readwrite (  distsize_t    offset, int    size )  [virtual]   Only one thread can have an unreleased obtain_readwrite at a time. The actual memory region locked can be larger than that requested. If the memory region is already locked this will block. For this reason, data should be held as read/write for as short a time as possible. Implements sc::MemoryGrp. void sc::ShmMemoryGrp::release_readwrite (  void *    data, distsize_t    offset, int    size )  [virtual]   This is called when read/write access is no longer needed. The memory will be unlocked. Implements sc::MemoryGrp. void sc::ShmMemoryGrp::set_localsize (  size_t    )  [virtual]   Set the size of locally held memory. When memory is accessed using a global offset counting starts at node 0 and proceeds up to node n() - 1. Reimplemented from sc::MsgMemoryGrp. The documentation for this class was generated from the following file: memshm.h