详细描述

Transport configuration for the shm:// Iceoryx shared-memory transport.

ShmConf binds the shm:// URL scheme to the Eclipse Iceoryx zero-copy shared-memory transport. Publishers loan() a memory chunk directly from the RouDi-managed memory pool, fill it in place, and publish() it; subscribers receive the chunk by pointer and release it back to the pool when finished. No payload bytes are ever copied between processes, which makes this the lowest-latency option for large messages on a single host.

Shared-Memory Layout: RouDi (daemon)

+-----------------------------------------------+

| Mempool: fixed-size chunk segments |

| +------+ +------+ +------+ +------+ +------+ |

| | chk0 | | chk1 | | chk2 | | chk3 | | ... | |

| +------+ +------+ +------+ +------+ +------+ |

+--------^--------------------------^-----------+

| loan() | release()

| |

Publisher process Subscriber process

Loan / Release Flow: Publisher: chunk = loan(size); fill(chunk); publish(chunk);

\

\--> queue (per topic in RouDi)

\

Subscriber: chunk = take(); \--> chunk arrival

consume(chunk); release(chunk);

Supported Node Types

Publisher	Subscriber	Server	Client	Getter	Setter
yes	yes	yes	yes	yes	yes

URL Format: shm://<address>[?event=<name>&domain=<N>&depth=<N>&history=<N>&wait=<ms>]

Component	Description
`address`	Iceoryx service/topic name (URL host concatenated with path)
`event`	Optional secondary event name (?event=)
`domain`	Iceoryx domain ID (?domain=); defaults to `0`
`depth`	Queue capacity override; `0` uses the Iceoryx default
`history`	History count (?history=); `0` from URL, or `1` for field nodes
`wait`	Blocking-wait timeout in ms for pub/sub; not valid for RPC or fields

RouDi Lifecycle: RouDi is the Iceoryx memory-manager daemon. It can either be started externally (preferred for production) or hosted in-process for tests and single-process tools.
// Option A: embedded RouDi (single-process tools):

vlink::ShmConf::init_roudi();

// Option B: connect this process to an external RouDi daemon:

vlink::ShmConf::init_runtime("my_app");

// Option C: one-line preflight that picks whichever is needed:

vlink::ShmConf::auto_init_roudi();

// ... create shm:// nodes ...

vlink::ShmConf::deinit_runtime();

注解: Compiled only when VLINK_SUPPORT_SHM is defined.; Iceoryx caps address and event at 80 characters each.; wait mode is only valid for kPublisher / kSubscriber; using it with RPC or field nodes causes parse_protocol() to return false.