fix(process): make process.title work properly on Linux #25521
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On Linux, process.title should modify the process name visible in tools like `ps`, `top`, and `htop`. Previously, setting process.title only updated an internal variable but did not modify the actual process title that external tools see. This fix implements process.title properly on Linux by: 1. Storing the original argv buffer location during initialization 2. Overwriting the original argv memory when process.title is set (this is how /proc/self/cmdline is populated) 3. Using prctl(PR_SET_NAME) to set the thread name (shown in top/htop) This matches Node.js behavior, which uses libuv's implementation that does the same argv memory overwriting technique. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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Updated 5:05 PM PT - Dec 15th, 2025
@Jarred-Sumner, your commit 746cec1 is building: |
WalkthroughAdds Linux-specific process title support: records the original argv buffer and capacity, exposes a public ProcessTitleInfo with setTitle to overwrite argv and set the thread name, invokes it from Node's setTitle on Linux, and adds a Linux-only test that verifies /proc/self/cmdline reflects process.title. Changes
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| title.* = bun.String.cloneUTF8(str orelse "bun"); | ||
| } | ||
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| // TODO: https://github.com/nodejs/node/blob/master/deps/uv/src/unix/darwin-proctitle.c |
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is macos supported yet? otherwise shouldn't the todo still be present?
| import { beforeAll, describe, expect, it } from "bun:test"; | ||
| import { beforeAll, describe, expect, it, setDefaultTimeout } from "bun:test"; | ||
| import { bunEnv, bunExe, isASAN, isBroken, isMusl, isWindows, nodeExe, tmpdirSync } from "harness"; | ||
| import assert from "node:assert"; | ||
| import fs from "node:fs/promises"; | ||
| import { basename, join } from "path"; | ||
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| // Building native modules with node-gyp takes a long time | ||
| setDefaultTimeout(1000 * 60 * 5); // 5 minutes | ||
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The v8 test compiles native modules with node-gyp in the beforeAll hook, which takes much longer than the default 5 second timeout. This was causing the test to time out and fail on slower machines or CI. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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Summary
process.titleon Linux to actually modify the process name visible in tools likeps,top, andhtopprocess.titleonly updated an internal variable but did not change what external tools seeImplementation
process.titleis set, overwrite the original argv memory (this is how/proc/self/cmdlineis populated)prctl(PR_SET_NAME)to set the thread name (visible in top/htop's thread name column)This matches Node.js behavior, which uses libuv's implementation with the same argv memory overwriting technique.
Test plan
/proc/self/cmdlineon Linuxprocess.titletests still passbun run zig:check-allpasses (compiles on all platforms)🤖 Generated with Claude Code