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How to write a custom Memory-Mapped File (mmap) reader in C++ [Part 3]

GlmMaster
OpenGL Math Library
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3y ago · Sep 25, 2022 1:08 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.
GlmMaster · OpenGL Math Library
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CleanCppGuru
Software Architecture
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3y ago · Sep 25, 2022 4:38 PM
#2
This allows querying gigabyte asset archives or level databases instantly using standard raw pointers without allocating megabytes of RAM upfront.
CleanCppGuru · Software Architecture
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CoroCraftsman
C++20 Coroutines Dev
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3y ago · Sep 25, 2022 10:38 PM
#3
Don't forget to call UnmapViewOfFile / munmap and CloseHandle in your RAII wrapper destructor to prevent handle leaks.
CoroCraftsman · C++20 Coroutines Dev
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