Files
interprocess/doc/code/doc_where_allocate.cpp
Ion Gaztañaga 4ed08b24a6 First complete documentation version
[SVN r34817]
2006-08-04 19:14:25 +00:00

59 lines
2.5 KiB
C++

#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/interprocess/managed_shared_memory.hpp>
#include <boost/interprocess/containers/vector.hpp>
#include <boost/interprocess/containers/string.hpp>
#include <boost/interprocess/allocators/allocator.hpp>
int main ()
{
using namespace boost::interprocess;
//Typedefs
typedef allocator<char, managed_shared_memory::segment_manager>
CharAllocator;
typedef basic_string<char, std::char_traits<char>, CharAllocator>
MyShmString;
typedef allocator<MyShmString, managed_shared_memory::segment_manager>
StringAllocator;
typedef vector<MyShmString, StringAllocator>
MyShmStringVector;
//Open shared memory
shared_memory_object::remove("myshm");
managed_shared_memory shm(create_only, "myshm", 10000);
//Create allocators
CharAllocator charallocator (shm.get_segment_manager());
StringAllocator stringallocator(shm.get_segment_manager());
//This string is in only in this process (the pointer pointing to the
//buffer that will hold the text is not in shared memory).
//But the buffer that will hold "this is my text" is allocated from
//shared memory
MyShmString mystring(charallocator);
mystring = "this is my text";
//This vector is only in this process (the pointer pointing to the
//buffer that will hold the MyShmString-s is not in shared memory).
//But the buffer that will hold 10 MyShmString-s is allocated from
//shared memory using StringAllocator. Since strings use a shared
//memory allocator (CharAllocator) the 10 buffers that hold
//"this is my text" text are also in shared memory.
MyShmStringVector myvector(stringallocator);
myvector.insert(myvector.begin(), 10, mystring);
//This vector is fully constructed in shared memory. All pointers
//buffers are constructed in the same shared memory segment
//This vector can be safely accessed from other processes.
MyShmStringVector *myshmvector =
shm.construct<MyShmStringVector>("myshmvector")(stringallocator);
myshmvector->insert(myshmvector->begin(), 10, mystring);
//Destroy vector. This will free all strings that the vector contains
shm.destroy_ptr(myshmvector);
return 0;
}
#include <boost/interprocess/detail/config_end.hpp>