NAME
sysvipc - System V interprocess communication mechanisms
DESCRIPTION
System V IPC is the name given to three interprocess communication mechanisms that are widely available on UNIX systems: message queues, semaphore, and shared memory.
Message
queues
System V message queues allow data to be exchanged in units
called messages. Each messages can have an associated
priority, POSIX message queues provide an alternative API
for achieving the same result; see
mq_overview(7).
The System V
message queue API consists of the following system calls:
Create a new message queue or
obtain the ID of an existing message queue. This call
returns an identifier that is used in the remaining
APIs. Add a message to a queue. Remove a message from a
queue. Perform various control
operations on a queue, including deletion. Semaphore
sets The System V
semaphore API consists of the following system calls:
Create a new set or obtain the
ID of an existing set. This call returns an identifier that
is used in the remaining APIs. Perform operations on the
semaphores in a set. Perform various control
operations on a set, including deletion. Shared
memory segments The System V
shared memory API consists of the following system calls:
Create a new segment or obtain
the ID of an existing segment. This call returns an
identifier that is used in the remaining APIs. Attach an existing shared
memory object into the calling process’s address
space. Detach a segment from the
calling process’s address space. Perform various control
operations on a segment, including deletion. IPC
namespaces ipcmk(1),
ipcrm(1), ipcs(1), lsipc(1),
ipc(2), msgctl(2), msgget(2),
msgrcv(2), msgsnd(2), semctl(2),
semget(2), semop(2), shmat(2),
shmctl(2), shmdt(2), shmget(2),
ftok(3), ipc_namespaces(7)
This page is
part of release 5.09 of the Linux man-pages project.
A description of the project, information about reporting
bugs, and the latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
msgget(2)
System V semaphores allow processes to synchronize their
actions System V semaphores are allocated in groups called
sets; each semaphore in a set is a counting semaphore. POSIX
semaphores provide an alternative API for achieving the same
result; see sem_overview(7).
semget(2)
System V shared memory allows processes to share a region a
memory (a "segment"). POSIX shared memory is an
alternative API for achieving the same result; see
shm_overview(7).
shmget(2)
For a discussion of the interaction of System V IPC objects
and IPC namespaces, see ipc_namespaces(7).SEE ALSO
COLOPHON