BitLogger/docs/api/runtime-sink-file-write-failures.md

name, group, category, update-time, description, key-word

name	group	category	update-time	description	key-word
runtime-sink-file-write-failures	api	runtime	20260613	Read the number of write failures recorded by a file-backed RuntimeSink.	runtime sink file public

Runtime-sink-file-write-failures

Read the number of write failures recorded by a file-backed RuntimeSink. This helper is useful for direct runtime diagnostics around the file write path.

Interface

pub fn RuntimeSink::file_write_failures(self : RuntimeSink) -> Int {

input

• self : RuntimeSink - Runtime sink whose write-failure counter should be inspected.

output

• Int - Number of recorded write failures.

Explanation

Detailed rules explaining key parameters and behaviors

• Plain File runtime variants report the wrapped FileSink write-failure count.
• QueuedFile runtime variants forward the metric from the wrapped inner FileSink.
• For QueuedFile, enqueueing a record does not increment this counter by itself. The counter changes only when queued records are actually drained into the inner file sink, such as through file_flush().
• Non-file runtime variants return 0.
• The counter is cumulative until file_reset_failure_counters() clears it.

How to Use

Here are some specific examples provided.

When Need Runtime Write-path Diagnostics

When support output should show whether file writes have been failing:

let count = sink.file_write_failures()

In this example, callers get a focused signal for direct runtime file write-path health.

When Compare Sink Health After Recovery

When recovery logic should verify whether new failures still occur:

ignore(sink.file_write_failures())

In this example, the metric helps measure whether runtime writes improved after intervention.

Error Case

e.g.:

• If the runtime sink is not file-backed, the method returns 0.

• If callers need a fuller view of file health, file_state() or file_runtime_state() may be better APIs.

Notes

1. Use this helper for focused direct runtime write-failure visibility.

2. Pair it with file_flush() and file_flush_failures() when diagnosing queued output-path instability.