FileStreamTraceSink class final

A buffered line sink over file: truncates whatever a previous run left (ONE trace per file — each armed run replaces the last trail; collect across runs by copying the file between runs), then appends lines in batches. Concurrent armed runs share that one file: any second armed fa boot — another terminal, or a detached child that inherited FA_STREAM_TRACE (e.g. fa dap start spawning hub serve) — truncates the live trail at its install. Copy the file between runs when history matters. Batching keeps the per-mark cost off the hot stream path (a sync fsync per SSE chunk would perturb the very cadence being measured): lines flush on a flushInterval timer, when the buffer crosses _kFlushThresholdBytes, or on flush/dispose. The trade is explicit — up to one interval of buffered lines is lost on a hard kill. Diagnostics contract: an IO failure degrades to silence, never throws into the caller.

Implemented types

• StreamTraceSink

Constructors

FileStreamTraceSink(File _file, {Duration flushInterval = const Duration(milliseconds: 250)})

Truncates file for a fresh trace and arms the flush timer.

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

dispose() → void

Cancels the timer and flushes the tail. The CLI never calls this (the trace is process-lifetime); tests and embedders may.

flush() → void

Writes any buffered lines now (also driven by the flush timer).

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

writeLine(String line) → void

Receives one formatted trace body (no trailing newline).

override

Operators

operator ==(Object other) → bool

The equality operator.

inherited