shmopen
shm_open is a POSIX API function used to open or create a named shared memory object. It allows multiple processes to a priori share memory by agreeing on a common name and size, and then mapping that object into each process’s address space with mmap. The function returns a file descriptor that can be used for subsequent operations on the object, and the memory contents are shared among all processes that map the object.
The function prototype is int shm_open(const char *name, int oflag, mode_t mode). The name must begin with
After obtaining a descriptor, the size of the shared memory object must be set with ftruncate(fd, size).
Mapping the shared memory into a process uses mmap with MAP_SHARED and appropriate protections (e.g., PROT_READ |
shm_open is a core component of POSIX shared memory, contrasting with System V shared memory primitives. It