src: fix kill signal 0 on Windows

StefanStojanovic · marco-ippolito · commit fcd1622fc189 · 2025-06-05T11:12:07.000+02:00
This special case was missed in the previous changes to this file. Refs: #55514 Refs: #42923 Fixes: #57669 PR-URL: #57695 Reviewed-By: Luigi Pinca <luigipinca@gmail.com> Reviewed-By: Jake Yuesong Li <jake.yuesong@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Richard Lau <rlau@redhat.com>
diff --git a/src/process_wrap.cc b/src/process_wrap.cc
@@ -314,7 +314,7 @@ class ProcessWrap : public HandleWrap {
     int signal = args[0]->Int32Value(env->context()).FromJust();
 #ifdef _WIN32
     if (signal != SIGKILL && signal != SIGTERM && signal != SIGINT &&
-        signal != SIGQUIT) {
+        signal != SIGQUIT && signal != 0) {
       signal = SIGKILL;
     }
 #endif
diff --git a/test/parallel/test-child-process-kill.js b/test/parallel/test-child-process-kill.js
@@ -58,3 +58,23 @@ if (common.isWindows) {
   });
   process.kill('SIGHUP');
 }
+
+// Test that the process is not killed when sending a 0 signal.
+// This is a no-op signal that is used to check if the process is alive.
+const code = `const interval = setInterval(() => {}, 1000);
+process.stdin.on('data', () => { clearInterval(interval); });
+process.stdout.write('x');`;
+
+const checkProcess = spawn(process.execPath, ['-e', code]);
+
+checkProcess.on('exit', (code, signal) => {
+  assert.strictEqual(code, 0);
+  assert.strictEqual(signal, null);
+});
+
+checkProcess.stdout.on('data', common.mustCall((chunk) => {
+  assert.strictEqual(chunk.toString(), 'x');
+  checkProcess.kill(0);
+  checkProcess.stdin.write('x');
+  checkProcess.stdin.end();
+}));

Original file line number	Diff line number	Diff line change
`@@ -314,7 +314,7 @@ class ProcessWrap : public HandleWrap {`
`314`	`314`	`int signal = args[0]->Int32Value(env->context()).FromJust();`
`315`	`315`	`#ifdef _WIN32`
`316`	`316`	`if (signal != SIGKILL && signal != SIGTERM && signal != SIGINT &&`
`317`		`- signal != SIGQUIT) {`
	`317`	`+ signal != SIGQUIT && signal != 0) {`
`318`	`318`	`signal = SIGKILL;`
`319`	`319`	`}`
`320`	`320`	`#endif`