File-sink-set-policy

Apply a bundled runtime file policy update to a FileSink. This helper updates append mode, auto-flush, and rotation together through one policy object on the concrete sink.

Interface

pub fn FileSink::set_policy(self : FileSink, policy : FileSinkPolicy) -> Unit {

input

• self : FileSink - File sink whose runtime file policy should change.
• policy : FileSinkPolicy - Bundled runtime file policy to apply.

Explanation

Detailed rules explaining key parameters and behaviors

• This method copies policy.append, policy.auto_flush, and policy.rotation onto the sink.
• It updates the whole runtime file policy in one call instead of changing each field separately.
• It does not reopen the sink, rotate immediately, or report success with a return value.
• It is broader than set_append_mode(...), set_auto_flush(...), or set_rotation(...) because it applies all policy fields together.

How to Use

Here are some specific examples provided.

When Need Bundled Runtime Policy Changes

When append, flush, and rotation should change together on a direct file sink:

sink.set_policy(FileSinkPolicy::new(
  append=true,
  auto_flush=false,
  rotation=Some(file_rotation(2048, max_backups=2)),
))

In this example, runtime file behavior is updated as one cohesive policy change.

When Restore A Policy Snapshot

When a previously captured or computed policy should be reapplied:

sink.set_policy(policy)

In this example, callers can restore a whole policy object without splitting it into separate setter calls.

Error Case

e.g.:

• If callers only need to change one field, a narrower setter may be clearer.

• This helper does not report past open, write, flush, or rotation failures; inspect the failure counters or state() separately when diagnostics matter.

Notes

1. Use this helper when runtime file policy should be treated as one cohesive object.

2. It pairs naturally with policy() and default_policy().