* Sync tail read for reAppendSessionMetadata's external-writer check. * fstat on the already-open fd (no extra path lookup); reads the same * LITE_READ_BUF_SIZE window that readLiteMetadata scans. Returns empty * string on any error so callers fall through to unconditional behavior.
(fullPath: string)
| 2590 | * string on any error so callers fall through to unconditional behavior. |
| 2591 | */ |
| 2592 | function readFileTailSync(fullPath: string): string { |
| 2593 | let fd: number | undefined |
| 2594 | try { |
| 2595 | fd = openSync(fullPath, 'r') |
| 2596 | const st = fstatSync(fd) |
| 2597 | const tailOffset = Math.max(0, st.size - LITE_READ_BUF_SIZE) |
| 2598 | const buf = Buffer.allocUnsafe( |
| 2599 | Math.min(LITE_READ_BUF_SIZE, st.size - tailOffset), |
| 2600 | ) |
| 2601 | const bytesRead = readSync(fd, buf, 0, buf.length, tailOffset) |
| 2602 | return buf.toString('utf8', 0, bytesRead) |
| 2603 | } catch { |
| 2604 | return '' |
| 2605 | } finally { |
| 2606 | if (fd !== undefined) { |
| 2607 | try { |
| 2608 | closeSync(fd) |
| 2609 | } catch { |
| 2610 | // closeSync can throw; swallow to preserve return '' contract |
| 2611 | } |
| 2612 | } |
| 2613 | } |
| 2614 | } |
| 2615 | /* eslint-enable custom-rules/no-sync-fs */ |
| 2616 | |
| 2617 | export async function saveCustomTitle( |
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