Struct MappedSnapshotWriter 

pub struct MappedSnapshotWriter { /* private fields */ }

Writable file mapping of a shared consciousness snapshot (single writer).

Implementations

impl MappedSnapshotWriter

pub fn create(path: &Path) -> Result<Self, String>

Create (or truncate) the snapshot file and initialize its header.

pub fn open_or_create(path: &Path) -> Result<Self, String>

Open an existing snapshot file for writing, or create a fresh one — without truncating an existing live mapping.

This is what stream processes use: a second instance must never clobber the file out from under the first process’s mmap (truncating a mapped file invalidates the other mapping and can crash it). Each whole-copy write() is published under one odd/even seqlock window, so even concurrent writers produce complete, non-torn snapshots.

pub fn open(path: &Path) -> Result<Self, String>

Open an existing snapshot file for writing.

pub fn write(&self, data: &SnapshotData) -> Result<(), String>

Publish a full SnapshotData and flush the mapping.

pub fn begin_write(&self) -> Result<u64, String>

Begin an in-place write (mirrors SharedSnapshot::begin_write).

pub fn end_write(&self, expected: u64)

End an in-place write.

pub unsafe fn data_mut(&self) -> &mut SnapshotData

Exclusive data access while the seqlock is held.

Safety

Caller must hold the seqlock (begin_write, not yet end_write).