Module lock 

Exclusive file-lock infrastructure for SubX operations.

This module provides acquire_subx_lock, an async helper that acquires an exclusive advisory file lock on $CONFIG_DIR/subx/subx.lock with a 2-second timeout. The returned SubxLockGuard releases the lock on drop.

All commands that mutate match_cache.json or match_journal.json must acquire this lock before proceeding (Design Decision D9).

Structs

SubxLockGuard

RAII guard that holds an exclusive file lock on the SubX lock file.

Functions

acquire_subx_lock

Acquire the SubX exclusive file lock with a 2-second timeout.