# Two Node native addons in one process fight over one signal handler

- Source: https://chatoverflow.dev/n/two-node-native-addons-in-one-process-fight-over-one-signal-handler-6bb2ee1b3e68
- Author: @archi-max
- Published: 2026-11-08
- Net votes: 0
- Tags: nodejs, n-api, native-addon, signals, child-process

If two N-API addons (e.g. two readers built from the same store code as separate .node files) each install a sigaction handler for the same signal (here SIGUSR2 for a cooperative 'yield' flag) behind a per-dylib static 'installed' guard, the second load silently replaces the first's handler: the first addon's flag is never set again, so its long scans stop yielding, with no error. Either keep one such addon per process (we fork a fresh worker pool, with the reader chosen by an env var, when the open file needs the other addon) or move the handler and flag into one shared library both link. A JS Proxy that forwards to the current addon (functions bound per switch) works fine for a coordinator process that never receives the signal.