fs: fix close listener leak in FileHandle streams#64227

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Merged
nodejs-github-bot merged 2 commits into from
Aug 17, 2026
Merged

fs: fix close listener leak in FileHandle streams #64227

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fs: fix close listener leak in FileHandle streams
Y1D7NG Jul 1, 2026
8d811ea
fs: fix close listener leak in FileHandle streams
Y1D7NG Jul 1, 2026
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14 changes: 13 additions & 1 deletion lib/internal/fs/streams.js
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Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
stream[kHandle] = options.fd;
stream[kFs] = FileHandleOperations(stream[kHandle]);
stream[kHandle][kRef]();
options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

const onclose = FunctionPrototypeBind(stream.close, stream);
options.fd.on('close', onclose);
if (options.autoClose === false) {
function cleanup() {
options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.
options.fd[kUnref]();
}
stream.once('end', cleanup);
stream.once('finish', cleanup);
stream.once('error', cleanup);
Comment on lines +159 to +165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change
functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);

@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.

There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.

@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?

@davidje13davidje13Aug 9, 2026

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to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.

@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.

Could this PR be landed, or does it need clarification of the above comments first?

@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.

@Y1D7NGY1D7NGAug 10, 2026

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I think the listeners can be left to normal garbage collection

@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.

}

return options.fd.fd;
}

Expand Down
39 changes: 39 additions & 0 deletions test/parallel/test-fs-promises-file-handle-stream.js
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
);
}

async function validateReusedCreateReadStream() {
const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

const fileHandle = await open(filePath, 'r');
try {
await buffer(fileHandle.createReadStream({
start: 0,
end: 0,
autoClose: false,
}));
assert.strictEqual(fileHandle.listenerCount('close'), 0);

await buffer(fileHandle.createReadStream({
start: 1,
end: 1,
autoClose: false,
}));
assert.strictEqual(fileHandle.listenerCount('close'), 0);
} finally {
await fileHandle.close();
}
}

async function validateReusedCreateWriteStream() {
const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
const fileHandle = await open(filePath, 'w');
try {
const stream = fileHandle.createWriteStream({ autoClose: false });
stream.end('a');
await finished(stream);
assert.strictEqual(fileHandle.listenerCount('close'), 0);
} finally {
await fileHandle.close();
}
}

Promise.all([
validateWrite(),
validateRead(),
validateReusedCreateReadStream(),
validateReusedCreateWriteStream(),
]).then(common.mustCall());
Loading
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 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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fs: fix close listener leak in FileHandle streams#64227

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 Merged

nodejs-github-bot
merged 2 commits into

from

Aug 17, 2026
 Merged


fs: fix close listener leak in FileHandle streams
#64227
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96cae83

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026
8d811ea

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026

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14 changes: 13 additions & 1 deletion
lib/internal/fs/streams.js

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
 stream[kHandle] = options.fd;
 stream[kFs] = FileHandleOperations(stream[kHandle]);
 stream[kHandle][kRef]();
 options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

 const onclose = FunctionPrototypeBind(stream.close, stream);
 options.fd.on('close', onclose);
 if (options.autoClose === false) {
 function cleanup() {
 options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.

 options.fd[kUnref]();
 }
 stream.once('end', cleanup);
 stream.once('finish', cleanup);
 stream.once('error', cleanup);

Comment on lines

+159
 to 
+165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change

functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.
There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.
@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?
@davidje13davidje13Aug 9, 2026

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to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.
@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.
Could this PR be landed, or does it need clarification of the above comments first?
@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.
@Y1D7NGY1D7NGAug 10, 2026

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I think the listeners can be left to normal garbage collection
@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.
 }

 return options.fd.fd;
 }

Expand Down

39 changes: 39 additions & 0 deletions
test/parallel/test-fs-promises-file-handle-stream.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
 );
}

async function validateReusedCreateReadStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
 fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

 const fileHandle = await open(filePath, 'r');
 try {
 await buffer(fileHandle.createReadStream({
 start: 0,
 end: 0,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);

 await buffer(fileHandle.createReadStream({
 start: 1,
 end: 1,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

async function validateReusedCreateWriteStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
 const fileHandle = await open(filePath, 'w');
 try {
 const stream = fileHandle.createWriteStream({ autoClose: false });
 stream.end('a');
 await finished(stream);
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

Promise.all([
 validateWrite(),
 validateRead(),
 validateReusedCreateReadStream(),
 validateReusedCreateWriteStream(),
]).then(common.mustCall());
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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fs: fix close listener leak in FileHandle streams#64227

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 Merged

nodejs-github-bot
merged 2 commits into

from

Aug 17, 2026
 Merged


fs: fix close listener leak in FileHandle streams
#64227
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96cae83

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026
8d811ea

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026

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14 changes: 13 additions & 1 deletion
lib/internal/fs/streams.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
 stream[kHandle] = options.fd;
 stream[kFs] = FileHandleOperations(stream[kHandle]);
 stream[kHandle][kRef]();
 options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

 const onclose = FunctionPrototypeBind(stream.close, stream);
 options.fd.on('close', onclose);
 if (options.autoClose === false) {
 function cleanup() {
 options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.

 options.fd[kUnref]();
 }
 stream.once('end', cleanup);
 stream.once('finish', cleanup);
 stream.once('error', cleanup);

Comment on lines

+159
 to 
+165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change

functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.
There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.
@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?
@davidje13davidje13Aug 9, 2026

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to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.
@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.
Could this PR be landed, or does it need clarification of the above comments first?
@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.
@Y1D7NGY1D7NGAug 10, 2026

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I think the listeners can be left to normal garbage collection
@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.
 }

 return options.fd.fd;
 }

Expand Down

39 changes: 39 additions & 0 deletions
test/parallel/test-fs-promises-file-handle-stream.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
 );
}

async function validateReusedCreateReadStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
 fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

 const fileHandle = await open(filePath, 'r');
 try {
 await buffer(fileHandle.createReadStream({
 start: 0,
 end: 0,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);

 await buffer(fileHandle.createReadStream({
 start: 1,
 end: 1,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

async function validateReusedCreateWriteStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
 const fileHandle = await open(filePath, 'w');
 try {
 const stream = fileHandle.createWriteStream({ autoClose: false });
 stream.end('a');
 await finished(stream);
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

Promise.all([
 validateWrite(),
 validateRead(),
 validateReusedCreateReadStream(),
 validateReusedCreateWriteStream(),
]).then(common.mustCall());
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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fs: fix close listener leak in FileHandle streams#64227

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 Merged

nodejs-github-bot
merged 2 commits into

from

Aug 17, 2026
 Merged


fs: fix close listener leak in FileHandle streams
#64227
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96cae83

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026
8d811ea

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026

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14 changes: 13 additions & 1 deletion
lib/internal/fs/streams.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
 stream[kHandle] = options.fd;
 stream[kFs] = FileHandleOperations(stream[kHandle]);
 stream[kHandle][kRef]();
 options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

 const onclose = FunctionPrototypeBind(stream.close, stream);
 options.fd.on('close', onclose);
 if (options.autoClose === false) {
 function cleanup() {
 options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.

 options.fd[kUnref]();
 }
 stream.once('end', cleanup);
 stream.once('finish', cleanup);
 stream.once('error', cleanup);

Comment on lines

+159
 to 
+165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change

functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.
There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.
@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?
@davidje13davidje13Aug 9, 2026

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to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.
@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.
Could this PR be landed, or does it need clarification of the above comments first?
@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.
@Y1D7NGY1D7NGAug 10, 2026

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I think the listeners can be left to normal garbage collection
@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.
 }

 return options.fd.fd;
 }

Expand Down

39 changes: 39 additions & 0 deletions
test/parallel/test-fs-promises-file-handle-stream.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
 );
}

async function validateReusedCreateReadStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
 fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

 const fileHandle = await open(filePath, 'r');
 try {
 await buffer(fileHandle.createReadStream({
 start: 0,
 end: 0,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);

 await buffer(fileHandle.createReadStream({
 start: 1,
 end: 1,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

async function validateReusedCreateWriteStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
 const fileHandle = await open(filePath, 'w');
 try {
 const stream = fileHandle.createWriteStream({ autoClose: false });
 stream.end('a');
 await finished(stream);
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

Promise.all([
 validateWrite(),
 validateRead(),
 validateReusedCreateReadStream(),
 validateReusedCreateWriteStream(),
]).then(common.mustCall());
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
fs: fix close listener leak in FileHandle streams#64227

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merged 2 commits into

from

Aug 17, 2026
 Merged


fs: fix close listener leak in FileHandle streams
#64227
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96cae83

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026
8d811ea

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026

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14 changes: 13 additions & 1 deletion
lib/internal/fs/streams.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
 stream[kHandle] = options.fd;
 stream[kFs] = FileHandleOperations(stream[kHandle]);
 stream[kHandle][kRef]();
 options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

 const onclose = FunctionPrototypeBind(stream.close, stream);
 options.fd.on('close', onclose);
 if (options.autoClose === false) {
 function cleanup() {
 options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.

 options.fd[kUnref]();
 }
 stream.once('end', cleanup);
 stream.once('finish', cleanup);
 stream.once('error', cleanup);

Comment on lines

+159
 to 
+165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change

functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.
There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.
@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?
@davidje13davidje13Aug 9, 2026

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to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.
@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.
Could this PR be landed, or does it need clarification of the above comments first?
@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.
@Y1D7NGY1D7NGAug 10, 2026

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I think the listeners can be left to normal garbage collection
@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.
 }

 return options.fd.fd;
 }

Expand Down

39 changes: 39 additions & 0 deletions
test/parallel/test-fs-promises-file-handle-stream.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
 );
}

async function validateReusedCreateReadStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
 fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

 const fileHandle = await open(filePath, 'r');
 try {
 await buffer(fileHandle.createReadStream({
 start: 0,
 end: 0,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);

 await buffer(fileHandle.createReadStream({
 start: 1,
 end: 1,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

async function validateReusedCreateWriteStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
 const fileHandle = await open(filePath, 'w');
 try {
 const stream = fileHandle.createWriteStream({ autoClose: false });
 stream.end('a');
 await finished(stream);
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

Promise.all([
 validateWrite(),
 validateRead(),
 validateReusedCreateReadStream(),
 validateReusedCreateWriteStream(),
]).then(common.mustCall());
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fs: fix close listener leak in FileHandle streams#64227

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to your account

 Merged

nodejs-github-bot
merged 2 commits into

from

Aug 17, 2026
 Merged


fs: fix close listener leak in FileHandle streams
#64227
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96cae83

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026
8d811ea

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026

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14 changes: 13 additions & 1 deletion
lib/internal/fs/streams.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
 stream[kHandle] = options.fd;
 stream[kFs] = FileHandleOperations(stream[kHandle]);
 stream[kHandle][kRef]();
 options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

 const onclose = FunctionPrototypeBind(stream.close, stream);
 options.fd.on('close', onclose);
 if (options.autoClose === false) {
 function cleanup() {
 options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.

 options.fd[kUnref]();
 }
 stream.once('end', cleanup);
 stream.once('finish', cleanup);
 stream.once('error', cleanup);

Comment on lines

+159
 to 
+165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change

functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.
There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.
@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?
@davidje13davidje13Aug 9, 2026

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to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.
@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.
Could this PR be landed, or does it need clarification of the above comments first?
@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.
@Y1D7NGY1D7NGAug 10, 2026

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I think the listeners can be left to normal garbage collection
@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.
 }

 return options.fd.fd;
 }

Expand Down

39 changes: 39 additions & 0 deletions
test/parallel/test-fs-promises-file-handle-stream.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
 );
}

async function validateReusedCreateReadStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
 fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

 const fileHandle = await open(filePath, 'r');
 try {
 await buffer(fileHandle.createReadStream({
 start: 0,
 end: 0,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);

 await buffer(fileHandle.createReadStream({
 start: 1,
 end: 1,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

async function validateReusedCreateWriteStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
 const fileHandle = await open(filePath, 'w');
 try {
 const stream = fileHandle.createWriteStream({ autoClose: false });
 stream.end('a');
 await finished(stream);
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

Promise.all([
 validateWrite(),
 validateRead(),
 validateReusedCreateReadStream(),
 validateReusedCreateWriteStream(),
]).then(common.mustCall());
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fs: fix close listener leak in FileHandle streams#64227

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Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
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to your account

 Merged

nodejs-github-bot
merged 2 commits into

from

Aug 17, 2026
 Merged


fs: fix close listener leak in FileHandle streams
#64227
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96cae83

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026
8d811ea

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026

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14 changes: 13 additions & 1 deletion
lib/internal/fs/streams.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
 stream[kHandle] = options.fd;
 stream[kFs] = FileHandleOperations(stream[kHandle]);
 stream[kHandle][kRef]();
 options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

 const onclose = FunctionPrototypeBind(stream.close, stream);
 options.fd.on('close', onclose);
 if (options.autoClose === false) {
 function cleanup() {
 options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.

 options.fd[kUnref]();
 }
 stream.once('end', cleanup);
 stream.once('finish', cleanup);
 stream.once('error', cleanup);

Comment on lines

+159
 to 
+165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change

functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.
There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.
@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?
@davidje13davidje13Aug 9, 2026

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Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.
@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.
Could this PR be landed, or does it need clarification of the above comments first?
@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.
@Y1D7NGY1D7NGAug 10, 2026

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ContributorAuthor
Choose a reason for hiding this comment

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I think the listeners can be left to normal garbage collection
@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.
 }

 return options.fd.fd;
 }

Expand Down

39 changes: 39 additions & 0 deletions
test/parallel/test-fs-promises-file-handle-stream.js

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
 );
}

async function validateReusedCreateReadStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
 fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

 const fileHandle = await open(filePath, 'r');
 try {
 await buffer(fileHandle.createReadStream({
 start: 0,
 end: 0,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);

 await buffer(fileHandle.createReadStream({
 start: 1,
 end: 1,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

async function validateReusedCreateWriteStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
 const fileHandle = await open(filePath, 'w');
 try {
 const stream = fileHandle.createWriteStream({ autoClose: false });
 stream.end('a');
 await finished(stream);
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

Promise.all([
 validateWrite(),
 validateRead(),
 validateReusedCreateReadStream(),
 validateReusedCreateWriteStream(),
]).then(common.mustCall());
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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fs: fix close listener leak in FileHandle streams#64227

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merged 2 commits into

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Aug 17, 2026
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fs: fix close listener leak in FileHandle streams
#64227
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96cae83

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026
8d811ea

fs: fix close listener leak in FileHandle streams


Y1D7NG Jul 1, 2026

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14 changes: 13 additions & 1 deletion
lib/internal/fs/streams.js

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Original file line numberDiff line numberDiff line change
Expand Up@@ -152,7 +152,19 @@ function importFd(stream, options) {
 stream[kHandle] = options.fd;
 stream[kFs] = FileHandleOperations(stream[kHandle]);
 stream[kHandle][kRef]();
 options.fd.on('close', FunctionPrototypeBind(stream.close, stream));

 const onclose = FunctionPrototypeBind(stream.close, stream);
 options.fd.on('close', onclose);
 if (options.autoClose === false) {
 function cleanup() {
 options.fd.removeListener('close', onclose);
Comment thread
ovflowd marked this conversation as resolved.

 options.fd[kUnref]();
 }
 stream.once('end', cleanup);
 stream.once('finish', cleanup);
 stream.once('error', cleanup);

Comment on lines

+159
 to 
+165

@atlowChemiatlowChemiAug 9, 2026

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@Y1D7NG should we removeListener for all 3 in cleanup, so we don't leave these hanging as well?

Suggested change

functioncleanup(){
options.fd.removeListener('close',onclose);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
functioncleanup(){
options.fd.removeListener('close',onclose);
stream.removeListener('end',cleanup);
stream.removeListener('finish',cleanup);
stream.removeListener('error',cleanup);
options.fd[kUnref]();
}
stream.once('end',cleanup);
stream.once('finish',cleanup);
stream.once('error',cleanup);
@davidje13davidje13Aug 9, 2026

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From what I'm aware of for similar functions, it's common practice to (intentionally) leave these listeners dangling on the stream and rely on normal garbage collection to tidy it all up in the end.
There was some discussion on this stuff in #35452. In this case, the duplex stuff doesn't apply so I'd personally say it doesn't need the special handling that was eventually added there.
@ovflowdovflowdAug 9, 2026

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Thanks for bringing that, that's interesting. Unsure how to proceed then. @nodejs/streams is the current behavior as expected?
@davidje13davidje13Aug 9, 2026

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to be clear: in my comment I'm only talking about the events on the stream (end/finish/error) - removing the close listener from the file descriptor (i.e. the purpose of this PR) is definitely necessary.
@MikeMcC399MikeMcC399Aug 10, 2026

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There are 2 approvals and a green CI.
Could this PR be landed, or does it need clarification of the above comments first?
@ovflowdovflowdAug 10, 2026

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My comments are non-blocking, although I don't see it hurting waiting extra time to get insights from the right team tho.
@Y1D7NGY1D7NGAug 10, 2026

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I think the listeners can be left to normal garbage collection
@MikeMcC399MikeMcC399Aug 17, 2026

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After waiting 7 days there haven't been any further comments, or any blocking objections, so adding to commit queue.
 }

 return options.fd.fd;
 }

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39 changes: 39 additions & 0 deletions
test/parallel/test-fs-promises-file-handle-stream.js

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Original file line numberDiff line numberDiff line change
Expand Up@@ -42,7 +42,46 @@ async function validateRead() {
 );
}

async function validateReusedCreateReadStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-stream.txt');
 fs.writeFileSync(filePath, Buffer.from('ab', 'utf8'));

 const fileHandle = await open(filePath, 'r');
 try {
 await buffer(fileHandle.createReadStream({
 start: 0,
 end: 0,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);

 await buffer(fileHandle.createReadStream({
 start: 1,
 end: 1,
 autoClose: false,
 }));
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

async function validateReusedCreateWriteStream() {
 const filePath = path.resolve(tmpDir, 'tmp-reused-write-stream.txt');
 const fileHandle = await open(filePath, 'w');
 try {
 const stream = fileHandle.createWriteStream({ autoClose: false });
 stream.end('a');
 await finished(stream);
 assert.strictEqual(fileHandle.listenerCount('close'), 0);
 } finally {
 await fileHandle.close();
 }
}

Promise.all([
 validateWrite(),
 validateRead(),
 validateReusedCreateReadStream(),
 validateReusedCreateWriteStream(),
]).then(common.mustCall());
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