VOID Shared Memory

Deterministic shared memory protocol for real-time numeric data exchange.

VOID Shared Memory (VOID SHM) defines a strict, versioned memory contract designed for ultra-low-latency communication between independent applications running on the same machine.

It is not a generic IPC framework. It is a deterministic shared state space.

Developed by Julien Bayle — Structure Void.

Max Package : macOS universal Binaries (intel/arm silicon)

TD Package : macOS universal Binaries (intel/arm silicon)

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Overview

VOID SHM enables:

• One writer → many readers topology
• Audio-rate, control-rate, or matrix-rate data
• Cross-application interoperability
• Explicit structural validation
• Predictable, debuggable real-time behavior

The system is based on POSIX shared memory and a strict binary layout.

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Core Concept

The model is explicit:

• A writer publishes structured numeric data into shared memory
• One or more readers consume snapshots of that state

Each memory segment is identified by name and follows a strict binary contract.

Writers define structure.
Readers validate and consume.

No implicit negotiation.

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The Shared Memory Contract (Header V2)

All segments follow the VOID Shared Memory Contract — currently Version 2.

Each segment begins with a fixed-size header containing:

• magic
• version
• header_size
• channels
• length
• epoch
• frame
• owner_app
• owner_project
• owner_node

The payload immediately follows the header and consists of:

float32 values arranged as channels × length

This structure is invariant across all connectors.

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Epoch / Frame Model

Two counters define temporal semantics.

Epoch

Represents a structural generation.

Any structural change (channels, length, name, connect state) triggers:

• hard reset
• epoch increment

Readers detect structural resets reliably.

Frame

Represents activity within a stable structure.

Each successful write increments the frame counter.

Readers can detect:

• activity
• stalling
• reconnection events

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Representation Model

VOID SHM uses a single invariant structure:

channels × length

This applies to all writers and readers.

There are no data-type conversions — only projections.

Examples:

• Signal writer → channels = signal count, length = 1
• Matrix writer → rows → channels, columns → length
• Reader → exposes signal lanes, matrix, or lists

Different views of the same structure.

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Connection Model

Connection is explicit and opt-in.

• Writers explicitly publish memory
• Readers explicitly attach
• No implicit writers
• No multi-writer conflicts

One writer per segment is enforced by design.

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Snapshot Semantics

Readers operate in strict snapshot mode:

1. open shared memory
2. validate header
3. read payload
4. close mapping

No persistent pointer across reads.

This prevents race conditions and stale views.

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Observability

Dedicated inspection tools allow:

• metadata inspection
• validity checks
• activity monitoring
• stall detection
• structural reset detection

This enables orchestration of complex multi-process systems.

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Design Philosophy

• determinism over convenience
• explicit control over automation
• structural clarity over abstraction
• debuggability over opacity
• local performance over network transparency

VOID SHM is intentionally minimal at the lowest level, so higher-level systems can remain expressive and reliable.

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Connectors

VOID SHM is protocol-first.
Connectors implement the same contract in different environments.

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Max Package (V2.x)

Includes:

• void.sm.writer
• void.sm.writer~
• void.sm.reader
• void.sm.reader~
• jit.void.sm.writer
• jit.void.sm.reader
• void.sm.info
• void.sm.state

Platforms:

• macOS (Intel / Apple Silicon)
• Windows (x64)

Distributed as a Max Package.

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TouchDesigner Connector (V2.x)

Includes:

• Custom CHOP reader
• Header V2 compliance
• Epoch-aware reconnection
• Deterministic channel mapping

Platforms:

• macOS (Intel / Apple Silicon)
• Windows (x64)

Distributed as a TouchDesigner plugin package.

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Future / Experimental Connectors

• openFrameworks
• Processing
• Standalone C++
• Additional real-time environments

All connectors must strictly comply with Header V2.

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Versioning

Releases follow semantic versioning :

• Major → protocol change
• Minor → implementation update
• Patch → bugfix

Protocol stability is prioritized over feature expansion.

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Downloads

See the Releases section of this repository.

Each release may contain environment-specific packages, for example:

• VOID-SHM-Max-vX.X.X.zip
• VOID-SHM-TouchDesigner-vX.X.X.zip

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License

Binary distribution.
Protocol specification public.
Implementation source code not distributed.

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Structure Void

VOID Shared Memory is developed as part of ongoing research and production systems in real-time audiovisual architecture.

https://structure-void.com