---
id: "bug-1617"
status: "fixed"
status_updated: "2026-09-24"
status_note: ""
component: "build"
severity: "unknown"
timestamp: "2026-08-21T00:00:00Z"
last_seen: "2026-09-19T09:00:00Z"
occurrences: 1
files: ["src/tools/test-dirty-fingerprint-nix-production-path.sh"]
tags: ["mktemp", "busybox", "coreutils", "portability", "dirty-content-fingerprint", "task-6.3", "src/tools"]
related: []
legacy: true
---

# bug-1617: mktemp: Invalid argument

## Description
mktemp: Invalid argument

## Environment
_Not recorded (migrated from buglog.json)._

## Reproduction
_Not recorded (migrated from buglog.json)._

## Root cause
Used a GNU-coreutils-only mktemp template shape (`.../name.XXXXXX.log`, trailing literal suffix after the X run) assuming GNU mktemp's rule that XXXXXX only needs to be present, with a literal suffix like `--suffix` allowed after it in some historical GNU versions. This sandbox's `mktemp` is BusyBox's implementation, which requires the template to literally END with XXXXXX (no trailing suffix at all, and no `--suffix` flag support either) -- confirmed via `mktemp --help` showing BusyBox v1.36.1's usage text.

## Fix
Dropped the `.log` suffix from the template entirely (`.../xce-dirty-fp-nix-build-A.XXXXXX` with nothing after the X run) rather than reaching for `--suffix` (also BusyBox-unsupported). The isolated worktree's own top-level mktemp template (no suffix) already worked correctly and was the right pattern to copy for the two new build-log mktemp calls.

## Verification
_Not recorded (migrated from buglog.json)._

## References
_Not recorded (migrated from buglog.json)._