Chrome puts its SingletonSocket under $TMPDIR and AF_UNIX paths cap at 104/108 bytes, so a
deep HERMES_HOME (profile homes, test homes) made the new scratch TMPDIR kill Chrome at
startup ("Socket path too long") — two browser test files went red on the branch and green
on main. hermes_constants.socket_safe_tmpdir() keeps the scratch root when it fits and falls
back to the OS root for sockets only; the browser env and the code kernel RPC socket use it.
check_no_tmp_literals walked git-ignored runner artifacts (test_durations.json) and failed on
whatever the last test run wrote; it now skips `git ls-files --others --ignored` paths.
run_tests_parallel created its per-file temp roots in the system temp dir and exported no
TMPDIR, so a full-suite run wrote gigabytes of fixtures to tmpfs (3,225 leftover roots, 9.9 GB,
were sitting in /tmp on the dev box). Roots now live under HERMES_HOME/cache/scratch/pytest and
the test process inherits TMPDIR=<root>, so the existing cleanup removes every temp file.
The seventeen remaining literals are container-side paths, AF_UNIX socket-path-limit
candidates on darwin, detection needles, guard regexes and guidance text that tells the
model to avoid /tmp. Each carries an inline `no-tmp: ok — <why>` so the reason lives
next to the line; the baseline keeps only a fenced tree listing where a marker would render.
scripts/check_no_tmp_literals.py flags /tmp path tokens in production code, skills,
docs and prompt strings (tests, CI workflows, Dockerfiles, lockfiles, i18n mirror,
code comments and docstrings exempt; ${TMPDIR:-/tmp} idiom exempt). Opt out one line
with 'no-tmp: ok — <why>' on the line or the line above. _BASELINE lists pre-existing
hits per file: growth fails, burn-down is advisory (--strict-baseline / --print-baseline
to refresh). Wired into lint.yml next to check_compat_pointers.
