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How to write a custom Memory-Mapped File (mmap) reader in C++ [Part 5]

CmakeCraft
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6y ago · Jan 10, 2020 2:48 PM
#1
Memory-mapped I/O (CreateFileMapping / MapViewOfFile on Windows, mmap on POSIX) maps file contents directly into the process virtual address space. The OS page cache reads file pages on-demand with zero buffer copies.
CmakeCraft · Build Systems Architect
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RingBufferRob
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6y ago · Jan 10, 2020 4:26 PM
#2
This allows querying gigabyte asset archives or level databases instantly using standard raw pointers without allocating megabytes of RAM upfront.
RingBufferRob · High-Speed IPC
Shared memory circular buffers with atomic sequence barriers acro...
StaticAssertDev
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6y ago · Jan 11, 2020 5:26 PM
#3
Don't forget to call UnmapViewOfFile / munmap and CloseHandle in your RAII wrapper destructor to prevent handle leaks.
StaticAssertDev · Compile-Time Verification
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