|SHMGET(2)||System Calls Manual||SHMGET(2)|
shmget — get
shared memory area identifier
size_t size, int shmflg);
returns the shared memory identifier associated with the key
A shared memory segment is created if either key is equal to IPC_PRIVATE, or key does not have a shared memory segment identifier associated with it, and the IPC_CREAT bit is set in shmflg.
If a new shared memory segment is created, the data structure associated with it (the shmid_ds structure, see shmctl(2)) is initialized as follows:
Upon successful completion a positive shared memory segment identifier is returned. Otherwise, -1 is returned and the global variable errno is set to indicate the error.
shmget() system call will fail if:
key, int size, int
All of these include files are necessary. The type of size has changed.
|August 17, 1995||macOS 14.1|