Shared memory #

Scope #

Mapping files into process memory (mmap(), munmap()).
Mapping visibility flags (MAP_SHARED, MAP_PRIVATE, MAP_ANONYMOUS).
Memory protection flags (PROT_READ, PROT_WRITE, PROT_EXEC, PROT_NONE).
Inter-Process Communication (IPC) via memory-mapped files.
Copy-on-Write mechanism in private mappings.
Disk synchronization (msync(), MS_SYNC, MS_ASYNC).
Process address space structure.
Debugging memory mappings on Linux (/proc/<pid>/maps).
Mapping inheritance and behavior on fork().
POSIX Shared Memory object lifecycle (shm_open(), ftruncate(), shm_unlink()).
SHM namespace (/dev/shm/).
Anonymous mappings for IPC between related processes.

Lecture Slides
Code samples
Supplementary reading: W.R. Stevens, Unix Network Programming, Vol. 2, 2nd Ed.: Interprocess Communications, Chapters:
- 12 (Shared Memory Introduction)
- 13 (Posix Shared Memory)
- 14 (System V Shared Memory)