NewCache returns Cache (SHM) by connectionString, connectionString indicate the shm location with uri format eg.

OpenKey open a shm which is already exists.

shmat: map/unmap shared memory, plase see man 2 shmat.

shmctl: shared memory control operations.

shmdt: map/unmap shared memory, plase see man 2 shmdt.

shmget: get shared memort area identifier, please see man 2 shmget.